1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
| #include<algorithm>
#include<iostream>
#include<iomanip>
#include<cstring>
#include<cstdlib>
#include<vector>
#include<cstdio>
#include<cmath>
#include<queue>
using namespace std;
inline const int Get_Int() {
int num=0,bj=1;
char x=getchar();
while(x<'0'||x>'9') {
if(x=='-')bj=-1;
x=getchar();
}
while(x>='0'&&x<='9') {
num=num*10+x-'0';
x=getchar();
}
return num*bj;
}
int t,n,m,w,used[1005],dist[1005];
bool inque[1005];
struct Edge {
int from,to,dist;
};
vector<Edge>edges[1005];
void AddEdge(int x,int y,int v) {
edges[x].push_back((Edge) {
x,y,v
});
}
bool Spfa() {
deque<int>Q;
memset(used,0,sizeof(used));
for(int i=1; i<=n; i++) {
dist[i]=0;
Q.push_back(i);
inque[i]=1;
used[i]=1;
}
while(!Q.empty()) {
int Now=Q.front();
Q.pop_front();
inque[Now]=0;
for(auto& e:edges[Now]) {
int Next=e.to;
if(dist[Next]>dist[Now]+e.dist) {
dist[Next]=dist[Now]+e.dist;
if(!inque[Next]) {
used[Next]++;
if(used[Next]==n)return false;
inque[Next]=1;
if(!Q.empty()&&dist[Next]<dist[Q.front()])Q.push_front(Next);
else Q.push_back(Next);
}
}
}
}
return true;
}
int main() {
t=Get_Int();
while(t--) {
for(int i=1; i<=n; i++)edges[i].clear();
n=Get_Int();
m=Get_Int();
w=Get_Int();
for(int i=1; i<=m; i++) {
int x=Get_Int(),y=Get_Int(),v=Get_Int();
AddEdge(x,y,v);
AddEdge(y,x,v);
}
for(int i=1; i<=w; i++) {
int x=Get_Int(),y=Get_Int(),v=Get_Int();
AddEdge(x,y,-v);
}
puts(Spfa()?"NO":"YES");
}
return 0;
}
|
