Submission #421749

#	Time	Username	Problem	Language	Result	Execution time	Memory
421749		usachevd0	Packing Biscuits (IOI20_biscuits)	C++17	0 / 100	1096 ms	332 KiB

biscuits

#include <bits/stdc++.h>
#ifndef LOCAL
    #include "biscuits.h"
#endif

using namespace std;

#define fi first
#define se second
#define mp make_pair
#define pb push_back
#define all(a) (a).begin(), (a).end()
#define Time (clock() * 1.0 / CLOCKS_PER_SEC)
using ll = long long;
using ull = unsigned long long;
using pii = pair<int, int>;
using pil = pair<int, ll>;
using pli = pair<ll, int>;
using pll = pair<ll, ll>;
using ld = long double;
template<typename T1, typename T2> bool chkmin(T1& x, T2 y) {
    return y < x ? (x = y, true) : false;
}
template<typename T1, typename T2> bool chkmax(T1& x, T2 y) {
    return y > x ? (x = y, true) : false;
}
void debug_out() {
    cerr << endl;
}
template<typename T1, typename... T2> void debug_out(T1 A, T2... B) {
    cerr << ' ' << A;
    debug_out(B...);
}
template<typename T> void mdebug_out(T* a, int n) {
    for (int i = 0; i < n; ++i)
        cerr << a[i] << ' ';
    cerr << endl;
}
#ifdef LOCAL
    #define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
    #define mdebug(a, n) cerr << #a << ": ", mdebug_out(a, n)
#else
    #define debug(...) 1337
    #define mdebug(a, n) 1337
#endif
template<typename T> ostream& operator << (ostream& stream, const vector<T>& v) {
    for (auto& e : v)
        stream << e << ' ';
    return stream;
}
template<typename T1, typename T2> ostream& operator << (ostream& stream, const pair<T1, T2>& p) {
    return stream << p.first << ' ' << p.second;
}


const ll INF64 = 1e18;

ll count_tastiness_stu(ll x, vector<ll> a) {
    int k = a.size();
    
    ll sum = 0;
    for (int i = 0; i < k; ++i)
        sum += (a[i] << i);
    
    auto good = [&](ll y) -> bool {
        vector<ll> b(all(a));
        int j = k - 1;
        for (int i = k - 1; i >= 0; --i) {
            chkmin(j, i);
            if ((y >> i) & 1) {
                ll need = x;
                for (; j >= 0; --j) {
                    if (b[j] >= need) {
                        b[j] -= need;
                        need = 0;
                        break;
                    }
                    need -= b[j];
                    b[j] = 0;
                    need *= 2;
                }
                if (need) return false;
            }
        }
        return true;
    };
    
    ll ans = 1;
    for (ll y = 1; y <= 200000 && x * y <= sum; ++y) {
        ans += good(y);
    }
    return ans;
}

ll b[60];
ll mem[(int)5e6];

ll count_tastiness(ll x, vector<ll> a) {
    int k = a.size();
    
    ll sum = 0;
    for (int i = 0; i < k; ++i)
        sum += (a[i] << i);
    
    ll ans = 0;
    int tot = 0;
    
    for (int i = 0; i < k; ++i)
        b[i] = a[i];
    ll cur = 0;
    function<void(int, int, int)> brute = [&](int i, int t, int mem_ptr) {
        if (i == -1) {
            // debug(cur);
            ++ans;
            return;
        }
        
        ll ans0 = ans;
        brute(i - 1, t, mem_ptr);
        ll dans = ans - ans0;
        
        ll need = x;
        int mem_ptr0 = mem_ptr;
        
        
        chkmin(t, i);
        if (t < i) {
            if (need > (INF64 >> (i - t)) + 1)
                t = -1;
            else
                need <<= (i - t);
        }
        
        int t0 = t;
        for (; t >= 0; --t) {
            mem[mem_ptr++] = b[t];
            if (b[t] >= need) {
                b[t] -= need;
                need = 0;
                while (t >= 0 && b[t] == 0)
                    --t;
                break;
            }
            need -= b[t];
            b[t] = 0;
            need *= 2;
            if (need > INF64) {
                break;
            }
        }
        if (!need) {
            if (1 || t < i) {
                cur ^= 1ll << i;
                brute(i - 1, t, mem_ptr);
                cur ^= 1ll << i;
            } else ans += dans;
        }
        chkmax(t, 0);
        for (; t <= t0; ++t) {
            b[t] = mem[--mem_ptr];
        }
    };
    int t = k - 1;
    while (t >= 0 && b[t] == 0)
        --t;
    brute(59, t, 0);
    return ans;
    
    // ll ans = 1;
    // for (ll y = 1; y <= 200000 && x * y <= sum; ++y) {
    //     ans += good(y);
    // }
    // return ans;
}


#ifdef LOCAL

mt19937 rng(228);
ll randll(ll L, ll R) {
    return rng() % (R - L + 1) + L;
}

int32_t main() {
    #ifdef LOCAL
        freopen("in", "r", stdin);
    #endif
    ios::sync_with_stdio(0);
    cin.tie(0);
    
    /*const ll C = 4;
    for (int test = 1; ; ++test) {
        ll x = 1;
        int k = 2;
        vector<ll> a(k);
        for (auto& x : a)
            x = randll(0, C);
        if (count_tastiness(x, a) != count_tastiness_stu(x, a)) {
            cout << "1\n";
            cout << x << ' ' << k << '\n';
            cout << a << '\n';
            exit(0);
        }
        if (test % 1000 == 0) debug(test);
    }/**/
    
    int q;
    assert(scanf("%d", &q) == 1);
    vector<int> k(q);
    vector<long long> x(q);
    vector<vector<long long>> a(q);
    vector<long long> results(q);
    for (int t = 0; t < q; t++) {
        assert(scanf("%d%lld", &k[t], &x[t]) == 2);
        a[t] = vector<long long>(k[t]);
        for (int i = 0; i < k[t]; i++) {
            assert(scanf("%lld", &a[t][i]) == 1);
        }
    }
    fclose(stdin);

    for (int t = 0; t < q; t++) {
        results[t] = count_tastiness(x[t], a[t]);
    }
    for (int t = 0; t < q; t++) {
        printf("%lld\n", results[t]);
    }
    fclose(stdout);
    
    
    return 0;
}


#endif

Compilation message (stderr)

biscuits.cpp:205:6: warning: "/*" within comment [-Wcomment]
  205 |     }/**/
      |       
biscuits.cpp: In lambda function:
biscuits.cpp:123:13: warning: unused variable 'mem_ptr0' [-Wunused-variable]
  123 |         int mem_ptr0 = mem_ptr;
      |             ^~~~~~~~
biscuits.cpp: In function 'll count_tastiness(ll, std::vector<long long int>)':
biscuits.cpp:106:9: warning: unused variable 'tot' [-Wunused-variable]
  106 |     int tot = 0;
      |         ^~~

• Subtask 1: 0 / 9
• Subtask 2: 0 / 12
• Subtask 3: 0 / 21
• Subtask 4: 0 / 35
• Subtask 5: 0 / 23