Submission #979134

#	Time	Username	Problem	Language	Result	Execution time	Memory
979134		Sharky	Travelling Merchant (APIO17_merchant)	C++17	100 / 100	186 ms	4316 KiB

merchant

#include <bits/stdc++.h>
using namespace std;

#define int long long
const int N = 101;
const int K = 1001;
const int INF = 1e18;

int n, m, k;
int dist[N][N], p[N][N], buy[N][K], sell[N][K];

bool check(int k) {
    vector<vector<int>> d(N, vector<int> (N, INF));
    for (int i = 1; i <= n; i++) for (int j = 1; j <= n; j++) {
        if (j != i && dist[i][j] != INF) {
            d[i][j] = k * min(dist[i][j], INF / k) - p[i][j];
        }
    }
    for (int x = 1; x <= n; x++) for (int i = 1; i <= n; i++) for (int j = 1; j <= n; j++) {
        if (d[i][x] < INF && d[x][j] < INF) d[i][j] = min(d[i][j], max(-INF, d[i][x] + d[x][j]));
    }
    for (int x = 1; x <= n; x++) if (d[x][x] <= 0) return true;
    return false;
}

int32_t main() {
    ios::sync_with_stdio(0); cin.tie(0);
    cin >> n >> m >> k;
    for (int i = 1; i <= n; i++) for (int j = 1; j <= k; j++) cin >> buy[i][j] >> sell[i][j];
    for (int i = 1; i <= n; i++) {
        for (int j = 1; j <= n; j++) {
            if (i == j) continue;
            for (int id = 1; id <= k; id++) {
                if (sell[j][id] == -1 || buy[i][id] == -1) continue;
                p[i][j] = max(p[i][j], sell[j][id] - buy[i][id]);
            }
        }
    }
    for (int i = 1; i <= n; i++) for (int j = 1; j <= n; j++) if (i != j) dist[i][j] = INF;
    for (int i = 1; i <= m; i++) {
        int u, v, w;
        cin >> u >> v >> w;
        dist[u][v] = min(dist[u][v], w);
    }
    for (int x = 1; x <= n; x++) for (int i = 1; i <= n; i++) for (int j = 1; j <= n; j++) dist[i][j] = min(dist[i][j], dist[i][x] + dist[x][j]);
    int lb = 0, rb = INF;
    while (lb < rb) {
        int mid = (lb + rb + 1) / 2;
        if (check(mid)) lb = mid;
        else rb = mid - 1;
    }
    cout << lb << '\n';
}

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