Wa#6#7#8#9,求调(必关)

#include<bits/stdc++.h>
using namespace std;
int tot
queue<int> c;
struct node
{
	int fir;
	int to;
	int quan;
}q[7005];
int head[2005],d[2005],sum[2005];
bool p[2005];
void add(int u,int v,int w)
{
	tot++;
	q[tot].fir=head[u];
	q[tot].to=v;
	q[tot].quan=w;
	head[u]=tot;
}
bool solve(int m)
{
	for(int i=1;i<=m;i++)
	{
		d[i]=1e9;
	}
	d[1]=0;
	c.push(1);
	p[1]=1;
	sum[1]++;
	while(!c.empty())
	{
		int a=c.front();
		c.pop();
		p[a]=0;
		//cout<<a<<endl;
		for(int i=head[a];i;i=q[i].fir)
		{
			int x=q[i].quan;
			int y=q[i].to;
			//cout<<d[y]<<" "<<d[a]<<" "<<x<<"\n";
			if(d[y]>d[a]+x)
			{
				d[y]=d[a]+x;
				//cout<<i<<" "<<y<<" "<<x<<endl;
				if(!p[i])
				{
					if(sum[y]+1>m)
					{
						memset(d,0,sizeof(d));
						memset(q,0,sizeof(q));
						memset(p,0,sizeof(p));
						memset(head,0,sizeof(head));
						memset(sum,0,sizeof(sum));
						tot=0;
						return true;
					}
					sum[y]++;
					p[y]=1;
					c.push(y);
				}
			}
		}
	}
	memset(d,0,sizeof(d));
	memset(q,0,sizeof(q));
	memset(p,0,sizeof(p));
	memset(head,0,sizeof(head));
	memset(sum,0,sizeof(sum));
	tot=0;
	return false;
}
int main()
{
	int n;
	cin>>n;
	while(n)
	{
		int a,b;
		cin>>a>>b;
		while(b)
		{
			int u,v,w;
			cin>>u>>v>>w;
			add(u,v,w);
			if(w>0)
			add(v,u,w);
			b--;
		}
		if(solve(a))
		printf("YES\n");
		else
		printf("NO\n");
		n--;
	}
	return 0;
 }