pku 2492 A Bug's Life

#include<stdio.h>
int set[2001],other[2001];
int find(int x)
{
if(x==set[x])
return x;
set[x]=find(set[x]);
return set[x];
}

void merge(int x,int y)
{
int fx=find(x);
int fy=find(y);
set[fx]=fy;
}

int main()
{
int t,n,m,i,x,y,fx,fy,mark,d;
scanf("%d\n",&t);
d=0;
while(t--)
{
d++;
scanf("%d%d",&n,&m);
for(i=0;i<n+1;i++)
{
set[i]=i;
other[i]=0;
}
mark=0;
while(m--)
{
scanf("%d%d",&x,&y);
if(!mark)
{
fx=find(x);
fy=find(y);
if(fx==fy)
mark=1;
else
{
if(other[x])
{
merge(other[x],y);
}
else if(other[y])
{
merge(other[y],x);
}
else
{
other[x]=y;
other[y]=x;
}
}
}
}
printf("Scenario #%d:\n",d);
if(mark)
printf("Suspicious bugs found!\n");
else
printf("No suspicious bugs found!\n");
printf("\n");
}
return 0;
}