奶牛身高

#include<cstdio>      #include<string>      #include<cstring> #include<iostream>   #include<algorithm>    #include<cmath>using namespace std;      int n,m;int w;int f[199999];int q[199999],ff;int find(int x){    if(f[x]==x) return x;    int fx=find(f[x]);    q[x]+=q[f[x]];    return f[x]=fx;} int main()      {          scanf("%d",&w);    while(w--)    {        scanf("%d%d",&n,&m);        for(int i=1;i<=n;i++)        f[i]=i,q[i]=0;ff=0;        for(int i=1;i<=m;i++)        {            int x,y,z;            scanf("%d%d%d",&x,&y,&z);            if(ff==1) continue;            int fx=find(x);            int fy=find(y);            if(fx==fy)            {            //  printf("%d %d\n",q[y]-q[x],z);                if(q[y]-q[x]!=z) printf("Bessie is blind.\n"),ff=1;            }             else f[fy]=fx,q[fy]=-q[y]+q[x]+z;        }           if(ff==0) printf("Bessie's eyes are good\n");    }}