Submission #132930

#	Time	Username	Problem	Language	Result	Execution time	Memory
132930		12tqian	Strange Device (APIO19_strange_device)	C++14	100 / 100	1097 ms	80964 KiB

strange_device

#pragma comment(linker, "/stack:200000000")
//#pragma GCC optimize("Ofast")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#pragma GCC optimize ("O3")
#pragma GCC target ("sse4")
#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;
template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>;

const double PI = 4 * atan(1);

#define sz(x) (int)(x).size()
#define ll long long
#define ld long double
#define mp make_pair
#define pb push_back
#define eb emplace_back
#define pii pair <int, int>
#define vi vector<int>
#define f first
#define s second
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()
#define vpi vector<pair<int, int>>
#define vpd vector<pair<double, double>>
#define pd pair<double, double>

#define f0r(i,a) for(int i=0;i<a;i++)
#define f1r(i,a,b) for(int i=a;i<b;i++)
#define trav(a, x) for (auto& a : x)

void fast_io(){
    ios_base::sync_with_stdio(0);
    cin.tie(NULL);
    cout.tie(NULL);
}
void io(string taskname){
    string fin = taskname + ".in";
    string fout = taskname + ".out";
    const char* FIN = fin.c_str();
    const char* FOUT = fout.c_str();
    freopen(FIN, "r", stdin);
    freopen(FOUT, "w", stdout);
    fast_io();
}
const long long MOD = 1000003;
constexpr int base = 10;
constexpr int base_digits = 1;

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) { return *this = *this * v; }
    bigint &operator/=(const bigint &v) { return *this = *this / v; }

    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;
    }

};
set<pair<ll, ll>> s;
int main(){
    fast_io();
    ll n, a, b;
    cin >> n >> a >> b;
    bigint A = bigint(a);
    bigint B = bigint(b);

    ll mod = -1;
    bigint tmp = A*B/gcd(B+1, A);
    if(tmp<= bigint((ll) 1e18)){
        mod = tmp.longValue();
    }
    if(mod == -1){
        ll ans = 0;
        f0r(i, n){
            ll l, r;
            cin >> l >> r;
            ans += (r-l + 1);
        }
        cout << ans << endl;
        return 0;
    }
    f0r(i, n){
        ll l, r;
        cin >> l >> r;
        if(r-l>= mod-1){
            cout << mod << endl;
            return 0;
        }
        l%= mod;
        r%= mod;
        if(l>r){
            s.insert(mp(l, mod-1));
            s.insert(mp(0, r));
          //  cout << "here" << endl;
        }
        else{
            s.insert(mp(l, r));
        }
    }
    auto it1 = s.begin();
    auto it2 = s.begin();
    while(it1 != s.end()){
        it2 = next(it1);
        if(it2 == s.end()) break;
        if((*it2).s<=(*it1).s){
            s.erase(it2);
        }
        else{
            it1 = next(it1);
        }
    }

    vector<pair<ll, ll>> intervals;
    for(auto x: s) intervals.eb(x);
    ll ans = 0;
    f0r(i, sz(intervals)){
       // cout << intervals[i].f << " df " << intervals[i].s << endl;
        if(i == 0){
            ans += (intervals[i].s - intervals[i].f + 1);
        }
        else{
            ll l = intervals[i].f;
            ll r = intervals[i].s;
            ll lo = intervals[i-1].f;
            ll hi = intervals[i-1].s;
            if(r<= hi) continue;
            if(l>hi){
                ans += (r - l + 1);
            }
            else{
                ans += (r - hi);
            }
        }

    }
    cout << ans << endl;
    return 0;
}

Compilation message (stderr)

strange_device.cpp:1:0: warning: ignoring #pragma comment  [-Wunknown-pragmas]
 #pragma comment(linker, "/stack:200000000")
 
strange_device.cpp: In member function 'bigint& bigint::operator+=(const bigint&)':
strange_device.cpp:76:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             for (int i = 0, carry = 0; i < other.z.size() || carry; ++i) {
                                        ~~^~~~~~~~~~~~~~~~
strange_device.cpp:77:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
                 if (i == z.size())
                     ~~^~~~~~~~~~~
strange_device.cpp:79:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
                 z[i] += carry + (i < other.z.size() ? other.z[i] : 0);
                                  ~~^~~~~~~~~~~~~~~~
strange_device.cpp: In member function 'bigint& bigint::operator-=(const bigint&)':
strange_device.cpp:94:27: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
             if (sign == 1 && *this >= other || sign == -1 && *this <= other) {
                 ~~~~~~~~~~^~~~~~~~~~~~~~~~~
strange_device.cpp:95:46: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
                 for (int i = 0, carry = 0; i < other.z.size() || carry; ++i) {
                                            ~~^~~~~~~~~~~~~~~~
strange_device.cpp:96:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
                     z[i] -= carry + (i < other.z.size() ? other.z[i] : 0);
                                      ~~^~~~~~~~~~~~~~~~
strange_device.cpp: In member function 'bigint& bigint::operator*=(int)':
strange_device.cpp:116:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0, carry = 0; i < z.size() || carry; ++i) {
                                    ~~^~~~~~~~~~
strange_device.cpp:117:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             if (i == z.size())
                 ~~^~~~~~~~~~~
strange_device.cpp: In member function 'void bigint::read(const string&)':
strange_device.cpp:280:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         while (pos < s.size() && (s[pos] == '-' || s[pos] == '+')) {
                ~~~~^~~~~~~~~~
strange_device.cpp: In static member function 'static std::vector<int> bigint::convert_base(const std::vector<int>&, int, int)':
strange_device.cpp:312:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 1; i < p.size(); i++)
                         ~~^~~~~~~~~~
strange_device.cpp: In static member function 'static bigint::vll bigint::karatsubaMultiply(const vll&, const vll&)':
strange_device.cpp:359:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0; i < a1b1.size(); i++)
                         ~~^~~~~~~~~~~~~
strange_device.cpp:361:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0; i < a2b2.size(); i++)
                         ~~^~~~~~~~~~~~~
strange_device.cpp:364:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0; i < r.size(); i++)
                         ~~^~~~~~~~~~
strange_device.cpp:366:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0; i < a1b1.size(); i++)
                         ~~^~~~~~~~~~~~~
strange_device.cpp:368:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0; i < a2b2.size(); i++)
                         ~~^~~~~~~~~~~~~
strange_device.cpp: In member function 'bigint bigint::operator*(const bigint&) const':
strange_device.cpp:387:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0, carry = 0; i < c.size(); i++) {
                                    ~~^~~~~~~~~~
strange_device.cpp: In function 'int main()':
strange_device.cpp:463:16: warning: unused variable 'lo' [-Wunused-variable]
             ll lo = intervals[i-1].f;
                ^~
strange_device.cpp: In function 'void io(std::__cxx11::string)':
strange_device.cpp:47:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
     freopen(FIN, "r", stdin);
     ~~~~~~~^~~~~~~~~~~~~~~~~
strange_device.cpp:48:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
     freopen(FOUT, "w", stdout);
     ~~~~~~~^~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 5 / 5
• Subtask 3: 5 / 5
• Subtask 4: 5 / 5
• Subtask 5: 5 / 5
• Subtask 6: 20 / 20
• Subtask 7: 20 / 20
• Subtask 8: 30 / 30