Submission #820841

#	Time	Username	Problem	Language	Result	Execution time	Memory
820841		Alihan_8	Travelling Merchant (APIO17_merchant)	C++17	100 / 100	100 ms	4188 KiB

merchant

#include <bits/stdc++.h>

using namespace std;

#define all(x) x.begin(), x.end()
#define pb push_back
#define ln '\n'
#define int long long

template <class _T>
bool chmin(_T &x, const _T &y){
    bool flag = false;
    if ( x > y ){
        x = y; flag |= true;
    }
    return flag;
}

template <class _T>
bool chmax(_T &x, const _T &y){
    bool flag = false;
    if ( x < y ){
        x = y; flag |= true;
    }
    return flag;
}

signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    int n, m, k; cin >> n >> m >> k;
    vector <vector<int>> B(n, vector <int> (k)), S(n, vector <int> (k));
    for ( int i = 0; i < n; i++ ){
        for ( int j = 0; j < k; j++ ){
            cin >> B[i][j] >> S[i][j];
        }
    }
    const int inf = 1e9 + 501;
    vector <vector<int>> dis(n, vector <int> (n, inf));
    for ( int i = 0; i < m; i++ ){
        int u, v, t; cin >> u >> v >> t;
        dis[--u][--v] = t;
    }
    auto RunFloyd = [&](auto &d){
        for ( int i = 0; i < n; i++ ){
            for ( int j = 0; j < n; j++ ){
                for ( int k = 0; k < n; k++ ){
                    chmin(d[j][k], d[j][i] + d[i][k]);
                }
            }
        }
    };
    RunFloyd(dis);
    vector <vector<int>> P(n, vector <int> (n));
    for ( int i = 0; i < n; i++ ){
        for ( int j = 0; j < n; j++ ){
            for ( int _k = 0; _k < k; _k++ ){
                if ( B[i][_k] == -1 or S[j][_k] == -1 ){
                    continue;
                }
                chmax(P[i][j], -B[i][_k] + S[j][_k]);
            }
        }
    }
    auto ok = [&](int M){
        auto a = P;
        for ( int i = 0; i < n; i++ ){
            for ( int j = 0; j < n; j++ ){
                a[i][j] = M * dis[i][j] - P[i][j];
            }
        }
        RunFloyd(a);
        bool flag = false;
        for ( int i = 0; i < n; i++ ){
            flag |= (a[i][i] <= 0);
        }
        return flag;
    };
    int l = 0, r = 1e9 + 1;
    while ( l + 1 < r ){
        int md = (l + r) >> 1;
        if ( ok(md) ) l = md;
        else r = md;
    }
    cout << l;

    cout << '\n';
}

• Subtask 1: 12 / 12
• Subtask 2: 21 / 21
• Subtask 3: 33 / 33
• Subtask 4: 34 / 34