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38 lines
835 B
C++
38 lines
835 B
C++
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#include <bits/stdc++.h>
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using namespace std;
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int t, n, m, w, u, v, p, g[505][505];
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bool check() {
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for (int k = 1; k <= n; k++) {
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for (int i = 1; i <= n; i++) {
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for (int j = 1; j <= n; j++) {
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g[i][j] = min(g[i][j], g[i][k] + g[k][j]);
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}
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if (g[i][i] < 0) {
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return true;
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}
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}
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}
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return false;
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}
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int main() {
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cin >> t;
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while (t--) {
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memset(g, 0x3f, sizeof(g));
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cin >> n >> m >> w;
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for (int i = 1; i <= m; i++) {
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cin >> u >> v >> p;
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g[u][v] = g[v][u] = min(g[u][v], p);
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}
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for (int i = 1; i <= w; i++) {
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cin >> u >> v >> p;
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g[u][v] = min(g[u][v], -p);
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}
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cout << (check() ? "YES" : "NO") << endl;
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}
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return 0;
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}
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