@ clear123666
cnt[j]++应该放在if(!st[j])里边吧
原本：
```cpp
cnt[j]++;
if(cnt[j]>=n+1)return false;
if(!st[j]){
q.push(j);
st[j]=true;
}
```
应该为：
```cpp
if(!st[j]){
cnt[j]++;
if(cnt[j]>=n+1)return false;
q.push(j);
st[j]=true;
}
```
by superkkkeee @ 2024-04-04 17:59:10
@[clear123666](/user/1229671)
by superkkkeee @ 2024-04-04 17:59:37
@[superkkkeee](/user/777848)
谢谢你的指正，但#2 仍然是错的
[这是我的答题结果](https://www.luogu.com.cn/record/154287325)
by clear123666 @ 2024-04-04 19:07:04
@[clear123666](/user/1229671) 试试long long?
by superkkkeee @ 2024-04-04 19:09:07
改过了，你看看
```cpp
#include<iostream>
#include<algorithm>
#include<cstring>
#include<queue>
using namespace std;
#define int long long //here
const int N = 10010,M = 20010;
int e[M],ne[M],w[M],cnt[N],idx,h[N];
bool st[N];
int T;
int dist[N];
int n,m;
void add(int a,int b,int c){
e[idx]=b,w[idx]=c,ne[idx]=h[a],h[a]=idx++;
}
bool spfa(){
memset(dist,-0x3f,sizeof dist);
memset(st,0,sizeof st);
memset(cnt,0,sizeof cnt);
queue<int>q;
q.push(n+1);
dist[n+1]=0;
st[n+1]=true;
//cnt[n+1]++;
while(q.size()){
int t=q.front();
q.pop();
st[t]=false;
for(int i=h[t];~i;i=ne[i]){
int j=e[i];
if(dist[j]<dist[t]+w[i]){
dist[j]=dist[t]+w[i];
if(cnt[j]>=n+1)return false;
if(!st[j]){cnt[j]++; //here
q.push(j);
st[j]=true;
}
}
}
}
return true;
}
signed main(){
cin>>T;
while(T--){
idx=0;
memset(h,-1,sizeof h);
cin>>n>>m;
for(int i=1;i<=m;i++){
int a,b,c;
cin>>a>>b>>c;
add(a-1,b,c);
add(b,a-1,-c);
}
for(int i=0;i<=n;i++){
add(n+1,i,0);
}
if(!spfa())puts("false");
else puts("true");
}
return 0;
}
```
by superkkkeee @ 2024-04-04 19:11:55
@[superkkkeee](/user/777848)
貌似还是错的
[具体](https://www.luogu.com.cn/record/154287937)
by clear123666 @ 2024-04-04 19:12:05
改过了 @[clear123666](/user/1229671)
其实
```cpp
if(cnt[j]>=n+1)return false;
```
并不用放在判断里
by superkkkeee @ 2024-04-04 19:18:24
@[superkkkeee](/user/777848)
[好像还是错的](https://www.luogu.com.cn/record/154288958)
by clear123666 @ 2024-04-04 19:21:05
[啊？？？](https://www.luogu.com.cn/record/154288294)
(本人小号)
by superkkkeee @ 2024-04-04 19:22:40
@[clear123666](/user/1229671)
by superkkkeee @ 2024-04-04 19:22:52