Submission #56261

#	Time	Username	Problem	Language	Result	Execution time	Memory
56261		Benq	Parrots (IOI11_parrots)	C++14	100 / 100	1018 ms	26896 KiB

encoder

#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>
 
using namespace std;
using namespace __gnu_pbds;
 
typedef long long ll;
typedef long double ld;
typedef complex<ld> cd;
 
typedef pair<int, int> pi;
typedef pair<ll,ll> pl;
typedef pair<ld,ld> pd;
 
typedef vector<int> vi;
typedef vector<ld> vd;
typedef vector<ll> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
typedef vector<cd> vcd;
 
template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>;
 
#define FOR(i, a, b) for (int i=a; i<(b); i++)
#define F0R(i, a) for (int i=0; i<(a); i++)
#define FORd(i,a,b) for (int i = (b)-1; i >= a; i--)
#define F0Rd(i,a) for (int i = (a)-1; i >= 0; i--)
 
#define sz(x) (int)(x).size()
#define mp make_pair
#define pb push_back
#define f first
#define s second
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()
 
const int MOD = 1000000007;
const ll INF = 1e18;
const int MX = 100001;
 
/*void output(int X) {
    cout << X << " ";
}
 
vi z;
 
void send(int X) {
    z.pb(X);
    // cout << X << "\n";
}*/
 
 
#include "encoder.h"
#include "encoderlib.h"
 
// base and base_digits must be consistent
constexpr int base = 1000000000;
constexpr int base_digits = 9;
 
struct bigint {
    // value == 0 is represented by empty z
    vector<int> z; // digits
 
    // sign == 1 <==> value >= 0
    // sign == -1 <==> value < 0
    int sign;
 
    bigint() : sign(1) {
    }
 
    bigint(long long v) {
        *this = v;
    }
 
    bigint &operator=(long long v) {
        sign = v < 0 ? -1 : 1;
        v *= sign;
        z.clear();
        for (; v > 0; v = v / base)
            z.push_back((int) (v % base));
        return *this;
    }
 
    bigint(const string &s) {
        read(s);
    }
 
    bigint &operator+=(const bigint &other) {
        if (sign == other.sign) {
            for (int i = 0, carry = 0; i < other.z.size() || carry; ++i) {
                if (i == z.size())
                    z.push_back(0);
                z[i] += carry + (i < other.z.size() ? other.z[i] : 0);
                carry = z[i] >= base;
                if (carry)
                    z[i] -= base;
            }
        } else if (other != 0 /* prevent infinite loop */) {
            *this -= -other;
        }
        return *this;
    }
 
    friend bigint operator+(bigint a, const bigint &b) {
        return a += b;
    }
 
    bigint &operator-=(const bigint &other) {
        if (sign == other.sign) {
            if (sign == 1 && *this >= other || sign == -1 && *this <= other) {
                for (int i = 0, carry = 0; i < other.z.size() || carry; ++i) {
                    z[i] -= carry + (i < other.z.size() ? other.z[i] : 0);
                    carry = z[i] < 0;
                    if (carry)
                        z[i] += base;
                }
                trim();
            } else {
                *this = other - *this;
                this->sign = -this->sign;
            }
        } else {
            *this += -other;
        }
        return *this;
    }
 
    friend bigint
 
    operator-(bigint a, const bigint &b) {
        return a -= b;
    }
 
    bigint &operator*=(int v) {
        if (v < 0)
            sign = -sign, v = -v;
        for (int i = 0, carry = 0; i < z.size() || carry; ++i) {
            if (i == z.size())
                z.push_back(0);
            long long cur = (long long) z[i] * v + carry;
            carry = (int) (cur / base);
            z[i] = (int) (cur % base);
        }
        trim();
        return *this;
    }
 
    bigint operator*(int v) const {
        return bigint(*this) *= v;
    }
 
    friend pair<bigint, bigint> divmod(const bigint &a1, const bigint &b1) {
        int norm = base / (b1.z.back() + 1);
        bigint a = a1.abs() * norm;
        bigint b = b1.abs() * norm;
        bigint q, r;
        q.z.resize(a.z.size());
 
        for (int i = (int) a.z.size() - 1; i >= 0; i--) {
            r *= base;
            r += a.z[i];
            int s1 = b.z.size() < r.z.size() ? r.z[b.z.size()] : 0;
            int s2 = b.z.size() - 1 < r.z.size() ? r.z[b.z.size() - 1] : 0;
            int d = (int) (((long long) s1 * base + s2) / b.z.back());
            r -= b * d;
            while (r < 0)
                r += b, --d;
            q.z[i] = d;
        }
 
        q.sign = a1.sign * b1.sign;
        r.sign = a1.sign;
        q.trim();
        r.trim();
        return {q, r / norm};
    }
 
    friend bigint sqrt(const bigint &a1) {
        bigint a = a1;
        while (a.z.empty() || a.z.size() % 2 == 1)
            a.z.push_back(0);
 
        int n = a.z.size();
 
        int firstDigit = (int) ::sqrt((double) a.z[n - 1] * base + a.z[n - 2]);
        int norm = base / (firstDigit + 1);
        a *= norm;
        a *= norm;
        while (a.z.empty() || a.z.size() % 2 == 1)
            a.z.push_back(0);
 
        bigint r = (long long) a.z[n - 1] * base + a.z[n - 2];
        firstDigit = (int) ::sqrt((double) a.z[n - 1] * base + a.z[n - 2]);
        int q = firstDigit;
        bigint res;
 
        for (int j = n / 2 - 1; j >= 0; j--) {
            for (;; --q) {
                bigint r1 = (r - (res * 2 * base + q) * q) * base * base +
                            (j > 0 ? (long long) a.z[2 * j - 1] * base + a.z[2 * j - 2] : 0);
                if (r1 >= 0) {
                    r = r1;
                    break;
                }
            }
            res *= base;
            res += q;
 
            if (j > 0) {
                int d1 = res.z.size() + 2 < r.z.size() ? r.z[res.z.size() + 2] : 0;
                int d2 = res.z.size() + 1 < r.z.size() ? r.z[res.z.size() + 1] : 0;
                int d3 = res.z.size() < r.z.size() ? r.z[res.z.size()] : 0;
                q = (int) (((long long) d1 * base * base + (long long) d2 * base + d3) / (firstDigit * 2));
            }
        }
 
        res.trim();
        return res / norm;
    }
 
    bigint operator/(const bigint &v) const {
        return divmod(*this, v).first;
    }
 
    bigint operator%(const bigint &v) const {
        return divmod(*this, v).second;
    }
 
    bigint &operator/=(int v) {
        if (v < 0)
            sign = -sign, v = -v;
        for (int i = (int) z.size() - 1, rem = 0; i >= 0; --i) {
            long long cur = z[i] + rem * (long long) base;
            z[i] = (int) (cur / v);
            rem = (int) (cur % v);
        }
        trim();
        return *this;
    }
 
    bigint operator/(int v) const {
        return bigint(*this) /= v;
    }
 
    int operator%(int v) const {
        if (v < 0)
            v = -v;
        int m = 0;
        for (int i = (int) z.size() - 1; i >= 0; --i)
            m = (int) ((z[i] + m * (long long) base) % v);
        return m * sign;
    }
 
    bigint &operator*=(const bigint &v) {
        *this = *this * v;
        return *this;
    }
 
    bigint &operator/=(const bigint &v) {
        *this = *this / v;
        return *this;
    }
 
    bool operator<(const bigint &v) const {
        if (sign != v.sign)
            return sign < v.sign;
        if (z.size() != v.z.size())
            return z.size() * sign < v.z.size() * v.sign;
        for (int i = (int) z.size() - 1; i >= 0; i--)
            if (z[i] != v.z[i])
                return z[i] * sign < v.z[i] * sign;
        return false;
    }
 
    bool operator>(const bigint &v) const {
        return v < *this;
    }
 
    bool operator<=(const bigint &v) const {
        return !(v < *this);
    }
 
    bool operator>=(const bigint &v) const {
        return !(*this < v);
    }
 
    bool operator==(const bigint &v) const {
        return !(*this < v) && !(v < *this);
    }
 
    bool operator!=(const bigint &v) const {
        return *this < v || v < *this;
    }
 
    void trim() {
        while (!z.empty() && z.back() == 0)
            z.pop_back();
        if (z.empty())
            sign = 1;
    }
 
    bool isZero() const {
        return z.empty();
    }
 
    friend bigint operator-(bigint v) {
        if (!v.z.empty())
            v.sign = -v.sign;
        return v;
    }
 
    bigint abs() const {
        return sign == 1 ? *this : -*this;
    }
 
    long long longValue() const {
        long long res = 0;
        for (int i = (int) z.size() - 1; i >= 0; i--)
            res = res * base + z[i];
        return res * sign;
    }
 
    friend bigint gcd(const bigint &a, const bigint &b) {
        return b.isZero() ? a : gcd(b, a % b);
    }
 
    friend bigint lcm(const bigint &a, const bigint &b) {
        return a / gcd(a, b) * b;
    }
 
    void read(const string &s) {
        sign = 1;
        z.clear();
        int pos = 0;
        while (pos < s.size() && (s[pos] == '-' || s[pos] == '+')) {
            if (s[pos] == '-')
                sign = -sign;
            ++pos;
        }
        for (int i = (int) s.size() - 1; i >= pos; i -= base_digits) {
            int x = 0;
            for (int j = max(pos, i - base_digits + 1); j <= i; j++)
                x = x * 10 + s[j] - '0';
            z.push_back(x);
        }
        trim();
    }
 
    friend istream &operator>>(istream &stream, bigint &v) {
        string s;
        stream >> s;
        v.read(s);
        return stream;
    }
 
    friend ostream &operator<<(ostream &stream, const bigint &v) {
        if (v.sign == -1)
            stream << '-';
        stream << (v.z.empty() ? 0 : v.z.back());
        for (int i = (int) v.z.size() - 2; i >= 0; --i)
            stream << setw(base_digits) << setfill('0') << v.z[i];
        return stream;
    }
 
    static vector<int> convert_base(const vector<int> &a, int old_digits, int new_digits) {
        vector<long long> p(max(old_digits, new_digits) + 1);
        p[0] = 1;
        for (int i = 1; i < p.size(); i++)
            p[i] = p[i - 1] * 10;
        vector<int> res;
        long long cur = 0;
        int cur_digits = 0;
        for (int v : a) {
            cur += v * p[cur_digits];
            cur_digits += old_digits;
            while (cur_digits >= new_digits) {
                res.push_back(int(cur % p[new_digits]));
                cur /= p[new_digits];
                cur_digits -= new_digits;
            }
        }
        res.push_back((int) cur);
        while (!res.empty() && res.back() == 0)
            res.pop_back();
        return res;
    }
 
    typedef vector<long long> vll;
 
    static vll karatsubaMultiply(const vll &a, const vll &b) {
        int n = a.size();
        vll res(n + n);
        if (n <= 32) {
            for (int i = 0; i < n; i++)
                for (int j = 0; j < n; j++)
                    res[i + j] += a[i] * b[j];
            return res;
        }
 
        int k = n >> 1;
        vll a1(a.begin(), a.begin() + k);
        vll a2(a.begin() + k, a.end());
        vll b1(b.begin(), b.begin() + k);
        vll b2(b.begin() + k, b.end());
 
        vll a1b1 = karatsubaMultiply(a1, b1);
        vll a2b2 = karatsubaMultiply(a2, b2);
 
        for (int i = 0; i < k; i++)
            a2[i] += a1[i];
        for (int i = 0; i < k; i++)
            b2[i] += b1[i];
 
        vll r = karatsubaMultiply(a2, b2);
        for (int i = 0; i < a1b1.size(); i++)
            r[i] -= a1b1[i];
        for (int i = 0; i < a2b2.size(); i++)
            r[i] -= a2b2[i];
 
        for (int i = 0; i < r.size(); i++)
            res[i + k] += r[i];
        for (int i = 0; i < a1b1.size(); i++)
            res[i] += a1b1[i];
        for (int i = 0; i < a2b2.size(); i++)
            res[i + n] += a2b2[i];
        return res;
    }
 
    bigint operator*(const bigint &v) const {
        vector<int> a6 = convert_base(this->z, base_digits, 6);
        vector<int> b6 = convert_base(v.z, base_digits, 6);
        vll a(a6.begin(), a6.end());
        vll b(b6.begin(), b6.end());
        while (a.size() < b.size())
            a.push_back(0);
        while (b.size() < a.size())
            b.push_back(0);
        while (a.size() & (a.size() - 1))
            a.push_back(0), b.push_back(0);
        vll c = karatsubaMultiply(a, b);
        bigint res;
        res.sign = sign * v.sign;
        for (int i = 0, carry = 0; i < c.size(); i++) {
            long long cur = c[i] + carry;
            res.z.push_back((int) (cur % 1000000));
            carry = (int) (cur / 1000000);
        }
        res.z = convert_base(res.z, 6, base_digits);
        res.trim();
        return res;
    }
 
};
 
bigint fac[600];
bool done[600][600];
bigint stor[600][600];
 
void init() {
    fac[0] = 1;
    FOR(i,1,600) fac[i] = fac[i-1]*i;
}
 
bigint comb(int a, int b) {
    return fac[a]/fac[b]/fac[a-b];
}
 
bigint getPosi(int num, int mn) {
    if (done[num][mn]) return stor[num][mn];
    done[num][mn] = 1;
    int range = 256-mn;
    stor[num][mn] = comb(num+range-1,range-1);
    return stor[num][mn];
}
 
/*bigint decodePermutation(int L, int* X) {
    int lst = 0;
    bigint ans(0);
    F0R(i,L) {
        FOR(j,lst,X[i]) ans += getPosi(L-1-i,j); 
        lst = X[i];
    }
    return ans;
}
 
void decode(int N, int L, int* X) {
    init();
    sort(X,X+L);
    bigint ans = decodePermutation(L,X);
    F0R(i,N) {
        output(ans % 256);
        ans /= 256;
    }
}*/
 
void encodePermutation(int N, bigint pos) {
    // how many below it = pos
    int NN = 5*N;
    int lst = 0;
    F0R(i,NN) {
        FOR(j,lst,256) {
            bigint t = getPosi(NN-1-i,j);
            if (t <= pos) {
                pos -= t;
            } else {
                send(j); lst = j;
                break;
            }
        }
    }
}
 
void encode(int N, int* M) {
    init();
    bigint pos(0), po(1), base(256);
    F0R(i,N) {
        pos += po*M[i];
        po = po*base;
    }
    encodePermutation(N,pos);
}

decoder

#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>
 
using namespace std;
using namespace __gnu_pbds;
 
typedef long long ll;
typedef long double ld;
typedef complex<ld> cd;
 
typedef pair<int, int> pi;
typedef pair<ll,ll> pl;
typedef pair<ld,ld> pd;
 
typedef vector<int> vi;
typedef vector<ld> vd;
typedef vector<ll> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
typedef vector<cd> vcd;
 
template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>;
 
#define FOR(i, a, b) for (int i=a; i<(b); i++)
#define F0R(i, a) for (int i=0; i<(a); i++)
#define FORd(i,a,b) for (int i = (b)-1; i >= a; i--)
#define F0Rd(i,a) for (int i = (a)-1; i >= 0; i--)
 
#define sz(x) (int)(x).size()
#define mp make_pair
#define pb push_back
#define f first
#define s second
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()
 
const int MOD = 1000000007;
const ll INF = 1e18;
const int MX = 100001;
 
/*void output(int X) {
    cout << X << " ";
}
 
vi z;
 
void send(int X) {
    z.pb(X);
    // cout << X << "\n";
}*/
 
 
#include "decoder.h"
#include "decoderlib.h"
 
// base and base_digits must be consistent
constexpr int base = 1000000000;
constexpr int base_digits = 9;
 
struct bigint {
    // value == 0 is represented by empty z
    vector<int> z; // digits
 
    // sign == 1 <==> value >= 0
    // sign == -1 <==> value < 0
    int sign;
 
    bigint() : sign(1) {
    }
 
    bigint(long long v) {
        *this = v;
    }
 
    bigint &operator=(long long v) {
        sign = v < 0 ? -1 : 1;
        v *= sign;
        z.clear();
        for (; v > 0; v = v / base)
            z.push_back((int) (v % base));
        return *this;
    }
 
    bigint(const string &s) {
        read(s);
    }
 
    bigint &operator+=(const bigint &other) {
        if (sign == other.sign) {
            for (int i = 0, carry = 0; i < other.z.size() || carry; ++i) {
                if (i == z.size())
                    z.push_back(0);
                z[i] += carry + (i < other.z.size() ? other.z[i] : 0);
                carry = z[i] >= base;
                if (carry)
                    z[i] -= base;
            }
        } else if (other != 0 /* prevent infinite loop */) {
            *this -= -other;
        }
        return *this;
    }
 
    friend bigint operator+(bigint a, const bigint &b) {
        return a += b;
    }
 
    bigint &operator-=(const bigint &other) {
        if (sign == other.sign) {
            if (sign == 1 && *this >= other || sign == -1 && *this <= other) {
                for (int i = 0, carry = 0; i < other.z.size() || carry; ++i) {
                    z[i] -= carry + (i < other.z.size() ? other.z[i] : 0);
                    carry = z[i] < 0;
                    if (carry)
                        z[i] += base;
                }
                trim();
            } else {
                *this = other - *this;
                this->sign = -this->sign;
            }
        } else {
            *this += -other;
        }
        return *this;
    }
 
    friend bigint
 
    operator-(bigint a, const bigint &b) {
        return a -= b;
    }
 
    bigint &operator*=(int v) {
        if (v < 0)
            sign = -sign, v = -v;
        for (int i = 0, carry = 0; i < z.size() || carry; ++i) {
            if (i == z.size())
                z.push_back(0);
            long long cur = (long long) z[i] * v + carry;
            carry = (int) (cur / base);
            z[i] = (int) (cur % base);
        }
        trim();
        return *this;
    }
 
    bigint operator*(int v) const {
        return bigint(*this) *= v;
    }
 
    friend pair<bigint, bigint> divmod(const bigint &a1, const bigint &b1) {
        int norm = base / (b1.z.back() + 1);
        bigint a = a1.abs() * norm;
        bigint b = b1.abs() * norm;
        bigint q, r;
        q.z.resize(a.z.size());
 
        for (int i = (int) a.z.size() - 1; i >= 0; i--) {
            r *= base;
            r += a.z[i];
            int s1 = b.z.size() < r.z.size() ? r.z[b.z.size()] : 0;
            int s2 = b.z.size() - 1 < r.z.size() ? r.z[b.z.size() - 1] : 0;
            int d = (int) (((long long) s1 * base + s2) / b.z.back());
            r -= b * d;
            while (r < 0)
                r += b, --d;
            q.z[i] = d;
        }
 
        q.sign = a1.sign * b1.sign;
        r.sign = a1.sign;
        q.trim();
        r.trim();
        return {q, r / norm};
    }
 
    friend bigint sqrt(const bigint &a1) {
        bigint a = a1;
        while (a.z.empty() || a.z.size() % 2 == 1)
            a.z.push_back(0);
 
        int n = a.z.size();
 
        int firstDigit = (int) ::sqrt((double) a.z[n - 1] * base + a.z[n - 2]);
        int norm = base / (firstDigit + 1);
        a *= norm;
        a *= norm;
        while (a.z.empty() || a.z.size() % 2 == 1)
            a.z.push_back(0);
 
        bigint r = (long long) a.z[n - 1] * base + a.z[n - 2];
        firstDigit = (int) ::sqrt((double) a.z[n - 1] * base + a.z[n - 2]);
        int q = firstDigit;
        bigint res;
 
        for (int j = n / 2 - 1; j >= 0; j--) {
            for (;; --q) {
                bigint r1 = (r - (res * 2 * base + q) * q) * base * base +
                            (j > 0 ? (long long) a.z[2 * j - 1] * base + a.z[2 * j - 2] : 0);
                if (r1 >= 0) {
                    r = r1;
                    break;
                }
            }
            res *= base;
            res += q;
 
            if (j > 0) {
                int d1 = res.z.size() + 2 < r.z.size() ? r.z[res.z.size() + 2] : 0;
                int d2 = res.z.size() + 1 < r.z.size() ? r.z[res.z.size() + 1] : 0;
                int d3 = res.z.size() < r.z.size() ? r.z[res.z.size()] : 0;
                q = (int) (((long long) d1 * base * base + (long long) d2 * base + d3) / (firstDigit * 2));
            }
        }
 
        res.trim();
        return res / norm;
    }
 
    bigint operator/(const bigint &v) const {
        return divmod(*this, v).first;
    }
 
    bigint operator%(const bigint &v) const {
        return divmod(*this, v).second;
    }
 
    bigint &operator/=(int v) {
        if (v < 0)
            sign = -sign, v = -v;
        for (int i = (int) z.size() - 1, rem = 0; i >= 0; --i) {
            long long cur = z[i] + rem * (long long) base;
            z[i] = (int) (cur / v);
            rem = (int) (cur % v);
        }
        trim();
        return *this;
    }
 
    bigint operator/(int v) const {
        return bigint(*this) /= v;
    }
 
    int operator%(int v) const {
        if (v < 0)
            v = -v;
        int m = 0;
        for (int i = (int) z.size() - 1; i >= 0; --i)
            m = (int) ((z[i] + m * (long long) base) % v);
        return m * sign;
    }
 
    bigint &operator*=(const bigint &v) {
        *this = *this * v;
        return *this;
    }
 
    bigint &operator/=(const bigint &v) {
        *this = *this / v;
        return *this;
    }
 
    bool operator<(const bigint &v) const {
        if (sign != v.sign)
            return sign < v.sign;
        if (z.size() != v.z.size())
            return z.size() * sign < v.z.size() * v.sign;
        for (int i = (int) z.size() - 1; i >= 0; i--)
            if (z[i] != v.z[i])
                return z[i] * sign < v.z[i] * sign;
        return false;
    }
 
    bool operator>(const bigint &v) const {
        return v < *this;
    }
 
    bool operator<=(const bigint &v) const {
        return !(v < *this);
    }
 
    bool operator>=(const bigint &v) const {
        return !(*this < v);
    }
 
    bool operator==(const bigint &v) const {
        return !(*this < v) && !(v < *this);
    }
 
    bool operator!=(const bigint &v) const {
        return *this < v || v < *this;
    }
 
    void trim() {
        while (!z.empty() && z.back() == 0)
            z.pop_back();
        if (z.empty())
            sign = 1;
    }
 
    bool isZero() const {
        return z.empty();
    }
 
    friend bigint operator-(bigint v) {
        if (!v.z.empty())
            v.sign = -v.sign;
        return v;
    }
 
    bigint abs() const {
        return sign == 1 ? *this : -*this;
    }
 
    long long longValue() const {
        long long res = 0;
        for (int i = (int) z.size() - 1; i >= 0; i--)
            res = res * base + z[i];
        return res * sign;
    }
 
    friend bigint gcd(const bigint &a, const bigint &b) {
        return b.isZero() ? a : gcd(b, a % b);
    }
 
    friend bigint lcm(const bigint &a, const bigint &b) {
        return a / gcd(a, b) * b;
    }
 
    void read(const string &s) {
        sign = 1;
        z.clear();
        int pos = 0;
        while (pos < s.size() && (s[pos] == '-' || s[pos] == '+')) {
            if (s[pos] == '-')
                sign = -sign;
            ++pos;
        }
        for (int i = (int) s.size() - 1; i >= pos; i -= base_digits) {
            int x = 0;
            for (int j = max(pos, i - base_digits + 1); j <= i; j++)
                x = x * 10 + s[j] - '0';
            z.push_back(x);
        }
        trim();
    }
 
    friend istream &operator>>(istream &stream, bigint &v) {
        string s;
        stream >> s;
        v.read(s);
        return stream;
    }
 
    friend ostream &operator<<(ostream &stream, const bigint &v) {
        if (v.sign == -1)
            stream << '-';
        stream << (v.z.empty() ? 0 : v.z.back());
        for (int i = (int) v.z.size() - 2; i >= 0; --i)
            stream << setw(base_digits) << setfill('0') << v.z[i];
        return stream;
    }
 
    static vector<int> convert_base(const vector<int> &a, int old_digits, int new_digits) {
        vector<long long> p(max(old_digits, new_digits) + 1);
        p[0] = 1;
        for (int i = 1; i < p.size(); i++)
            p[i] = p[i - 1] * 10;
        vector<int> res;
        long long cur = 0;
        int cur_digits = 0;
        for (int v : a) {
            cur += v * p[cur_digits];
            cur_digits += old_digits;
            while (cur_digits >= new_digits) {
                res.push_back(int(cur % p[new_digits]));
                cur /= p[new_digits];
                cur_digits -= new_digits;
            }
        }
        res.push_back((int) cur);
        while (!res.empty() && res.back() == 0)
            res.pop_back();
        return res;
    }
 
    typedef vector<long long> vll;
 
    static vll karatsubaMultiply(const vll &a, const vll &b) {
        int n = a.size();
        vll res(n + n);
        if (n <= 32) {
            for (int i = 0; i < n; i++)
                for (int j = 0; j < n; j++)
                    res[i + j] += a[i] * b[j];
            return res;
        }
 
        int k = n >> 1;
        vll a1(a.begin(), a.begin() + k);
        vll a2(a.begin() + k, a.end());
        vll b1(b.begin(), b.begin() + k);
        vll b2(b.begin() + k, b.end());
 
        vll a1b1 = karatsubaMultiply(a1, b1);
        vll a2b2 = karatsubaMultiply(a2, b2);
 
        for (int i = 0; i < k; i++)
            a2[i] += a1[i];
        for (int i = 0; i < k; i++)
            b2[i] += b1[i];
 
        vll r = karatsubaMultiply(a2, b2);
        for (int i = 0; i < a1b1.size(); i++)
            r[i] -= a1b1[i];
        for (int i = 0; i < a2b2.size(); i++)
            r[i] -= a2b2[i];
 
        for (int i = 0; i < r.size(); i++)
            res[i + k] += r[i];
        for (int i = 0; i < a1b1.size(); i++)
            res[i] += a1b1[i];
        for (int i = 0; i < a2b2.size(); i++)
            res[i + n] += a2b2[i];
        return res;
    }
 
    bigint operator*(const bigint &v) const {
        vector<int> a6 = convert_base(this->z, base_digits, 6);
        vector<int> b6 = convert_base(v.z, base_digits, 6);
        vll a(a6.begin(), a6.end());
        vll b(b6.begin(), b6.end());
        while (a.size() < b.size())
            a.push_back(0);
        while (b.size() < a.size())
            b.push_back(0);
        while (a.size() & (a.size() - 1))
            a.push_back(0), b.push_back(0);
        vll c = karatsubaMultiply(a, b);
        bigint res;
        res.sign = sign * v.sign;
        for (int i = 0, carry = 0; i < c.size(); i++) {
            long long cur = c[i] + carry;
            res.z.push_back((int) (cur % 1000000));
            carry = (int) (cur / 1000000);
        }
        res.z = convert_base(res.z, 6, base_digits);
        res.trim();
        return res;
    }
 
};
 
bigint fac[600];
bool done[600][600];
bigint stor[600][600];
 
void init() {
    fac[0] = 1;
    FOR(i,1,600) fac[i] = fac[i-1]*i;
}
 
bigint comb(int a, int b) {
    return fac[a]/fac[b]/fac[a-b];
}
 
bigint getPosi(int num, int mn) {
    if (done[num][mn]) return stor[num][mn];
    done[num][mn] = 1;
    int range = 256-mn;
    stor[num][mn] = comb(num+range-1,range-1);
    return stor[num][mn];
}
 
bigint decodePermutation(int L, int* X) {
    int lst = 0;
    bigint ans(0);
    F0R(i,L) {
        FOR(j,lst,X[i]) ans += getPosi(L-1-i,j); 
        lst = X[i];
    }
    return ans;
}
 
void decode(int N, int L, int* X) {
    init();
    sort(X,X+L);
    bigint ans = decodePermutation(L,X);
    F0R(i,N) {
        output(ans % 256);
        ans /= 256;
    }
}
 
/*void encodePermutation(int N, bigint pos) {
    // how many below it = pos
    int NN = 5*N;
    int lst = 0;
    F0R(i,NN) {
        FOR(j,lst,256) {
            bigint t = getPosi(NN-1-i,j);
            if (t <= pos) {
                pos -= t;
            } else {
                send(j); lst = j;
                break;
            }
        }
    }
}
 
void encode(int N, int* M) {
    init();
    bigint pos(0), po(1), base(256);
    F0R(i,N) {
        pos += po*M[i];
        po = po*base;
    }
    encodePermutation(N,pos);
}*/

Compilation message (stderr)

encoder.cpp: In member function 'bigint& bigint::operator+=(const bigint&)':
encoder.cpp:92:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             for (int i = 0, carry = 0; i < other.z.size() || carry; ++i) {
                                        ~~^~~~~~~~~~~~~~~~
encoder.cpp:93:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
                 if (i == z.size())
                     ~~^~~~~~~~~~~
encoder.cpp:95:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
                 z[i] += carry + (i < other.z.size() ? other.z[i] : 0);
                                  ~~^~~~~~~~~~~~~~~~
encoder.cpp: In member function 'bigint& bigint::operator-=(const bigint&)':
encoder.cpp:112:27: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
             if (sign == 1 && *this >= other || sign == -1 && *this <= other) {
                 ~~~~~~~~~~^~~~~~~~~~~~~~~~~
encoder.cpp:113:46: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
                 for (int i = 0, carry = 0; i < other.z.size() || carry; ++i) {
                                            ~~^~~~~~~~~~~~~~~~
encoder.cpp:114:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
                     z[i] -= carry + (i < other.z.size() ? other.z[i] : 0);
                                      ~~^~~~~~~~~~~~~~~~
encoder.cpp: In member function 'bigint& bigint::operator*=(int)':
encoder.cpp:139:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0, carry = 0; i < z.size() || carry; ++i) {
                                    ~~^~~~~~~~~~
encoder.cpp:140:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             if (i == z.size())
                 ~~^~~~~~~~~~~
encoder.cpp: In member function 'void bigint::read(const string&)':
encoder.cpp:337:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         while (pos < s.size() && (s[pos] == '-' || s[pos] == '+')) {
                ~~~~^~~~~~~~~~
encoder.cpp: In static member function 'static std::vector<int> bigint::convert_base(const std::vector<int>&, int, int)':
encoder.cpp:370:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 1; i < p.size(); i++)
                         ~~^~~~~~~~~~
encoder.cpp: In static member function 'static bigint::vll bigint::karatsubaMultiply(const vll&, const vll&)':
encoder.cpp:417:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0; i < a1b1.size(); i++)
                         ~~^~~~~~~~~~~~~
encoder.cpp:419:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0; i < a2b2.size(); i++)
                         ~~^~~~~~~~~~~~~
encoder.cpp:422:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0; i < r.size(); i++)
                         ~~^~~~~~~~~~
encoder.cpp:424:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0; i < a1b1.size(); i++)
                         ~~^~~~~~~~~~~~~
encoder.cpp:426:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0; i < a2b2.size(); i++)
                         ~~^~~~~~~~~~~~~
encoder.cpp: In member function 'bigint bigint::operator*(const bigint&) const':
encoder.cpp:445:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0, carry = 0; i < c.size(); i++) {
                                    ~~^~~~~~~~~~

decoder.cpp: In member function 'bigint& bigint::operator+=(const bigint&)':
decoder.cpp:92:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             for (int i = 0, carry = 0; i < other.z.size() || carry; ++i) {
                                        ~~^~~~~~~~~~~~~~~~
decoder.cpp:93:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
                 if (i == z.size())
                     ~~^~~~~~~~~~~
decoder.cpp:95:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
                 z[i] += carry + (i < other.z.size() ? other.z[i] : 0);
                                  ~~^~~~~~~~~~~~~~~~
decoder.cpp: In member function 'bigint& bigint::operator-=(const bigint&)':
decoder.cpp:112:27: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
             if (sign == 1 && *this >= other || sign == -1 && *this <= other) {
                 ~~~~~~~~~~^~~~~~~~~~~~~~~~~
decoder.cpp:113:46: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
                 for (int i = 0, carry = 0; i < other.z.size() || carry; ++i) {
                                            ~~^~~~~~~~~~~~~~~~
decoder.cpp:114:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
                     z[i] -= carry + (i < other.z.size() ? other.z[i] : 0);
                                      ~~^~~~~~~~~~~~~~~~
decoder.cpp: In member function 'bigint& bigint::operator*=(int)':
decoder.cpp:139:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0, carry = 0; i < z.size() || carry; ++i) {
                                    ~~^~~~~~~~~~
decoder.cpp:140:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             if (i == z.size())
                 ~~^~~~~~~~~~~
decoder.cpp: In member function 'void bigint::read(const string&)':
decoder.cpp:337:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         while (pos < s.size() && (s[pos] == '-' || s[pos] == '+')) {
                ~~~~^~~~~~~~~~
decoder.cpp: In static member function 'static std::vector<int> bigint::convert_base(const std::vector<int>&, int, int)':
decoder.cpp:370:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 1; i < p.size(); i++)
                         ~~^~~~~~~~~~
decoder.cpp: In static member function 'static bigint::vll bigint::karatsubaMultiply(const vll&, const vll&)':
decoder.cpp:417:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0; i < a1b1.size(); i++)
                         ~~^~~~~~~~~~~~~
decoder.cpp:419:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0; i < a2b2.size(); i++)
                         ~~^~~~~~~~~~~~~
decoder.cpp:422:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0; i < r.size(); i++)
                         ~~^~~~~~~~~~
decoder.cpp:424:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0; i < a1b1.size(); i++)
                         ~~^~~~~~~~~~~~~
decoder.cpp:426:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0; i < a2b2.size(); i++)
                         ~~^~~~~~~~~~~~~
decoder.cpp: In member function 'bigint bigint::operator*(const bigint&) const':
decoder.cpp:445:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0, carry = 0; i < c.size(); i++) {
                                    ~~^~~~~~~~~~

• Subtask 1: 17 / 17
• Subtask 2: 17 / 17
• Subtask 3: 18 / 18
• Subtask 4: 29 / 29
• Subtask 5: 19 / 19