【并查集】POJ_2492_A Bug's Life

2
3 3
1 2
2 3
1 3
4 2
1 2
3 4

Scenario #1:
Suspicious bugs found!

Scenario #2:
No suspicious bugs found!

#include <cstdio>
#include <cstring>
#include <algorithm>
using namespace std;
const int maxn=2010;
int f[maxn],val[maxn],n,m;
void Init(){
for(int i=0;i<=n;i++){
f[i]=i;
val[i]=0;
}
}
int Find(int x){
if(f[x]!=x){
int tmp=Find(f[x]);
val[x]^=val[f[x]];
f[x]=tmp;
}
return f[x];
}
int main(){
int t,x,y;
scanf("%d",&t);
for(int cas=1;cas<=t;cas++){
scanf("%d%d",&n,&m);
Init();
int flag=1;
while(m--){
scanf("%d%d",&x,&y);
int fx=Find(x);
int fy=Find(y);
if(fx==fy){
if(val[x]==val[y])
flag=0;
}
else {
f[fx]=fy;
val[fx]=~(val[x]^val[y]);
}
}
printf("Scenario #%d:\n",cas);
if(flag) printf("No suspicious bugs found!\n\n");
else printf("Suspicious bugs found!\n\n");
}
}