mirror of
https://git.sb/baoshuo/OI-codes.git
synced 2024-12-25 07:51:58 +00:00
57 lines
1.4 KiB
C++
57 lines
1.4 KiB
C++
#include <bits/stdc++.h>
|
|
|
|
using namespace std;
|
|
|
|
int f, n, m, w, u, v, t, dist[505], cnt[505];
|
|
vector<pair<int, int>> g[505];
|
|
bool vis[505];
|
|
|
|
bool spfa() {
|
|
memset(dist, 0x3f, sizeof(dist));
|
|
memset(vis, 0x00, sizeof(vis));
|
|
memset(cnt, 0x00, sizeof(cnt));
|
|
queue<int> q;
|
|
for (int i = 1; i <= n; i++) {
|
|
q.push(i);
|
|
vis[i] = true;
|
|
}
|
|
while (!q.empty()) {
|
|
int t = q.front();
|
|
q.pop();
|
|
vis[t] = false;
|
|
for (auto i : g[t]) {
|
|
if (dist[i.first] > dist[t] + i.second) {
|
|
dist[i.first] = dist[t] + i.second;
|
|
cnt[i.first] = cnt[t] + 1;
|
|
if (cnt[i.first] >= n) return true;
|
|
if (!vis[i.first]) {
|
|
q.push(i.first);
|
|
vis[i.first] = true;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
int main() {
|
|
cin >> f;
|
|
while (f--) {
|
|
cin >> n >> m >> w;
|
|
for (int i = 1; i <= n; i++) {
|
|
g[i].clear();
|
|
}
|
|
for (int i = 1; i <= m; i++) {
|
|
cin >> u >> v >> t;
|
|
g[u].push_back(make_pair(v, t));
|
|
g[v].push_back(make_pair(u, t));
|
|
}
|
|
for (int i = 1; i <= w; i++) {
|
|
cin >> u >> v >> t;
|
|
g[u].push_back(make_pair(v, -t));
|
|
}
|
|
cout << (spfa() ? "YES" : "NO") << endl;
|
|
}
|
|
return 0;
|
|
}
|