poj 1703

#include<stdio.h>
#include<string.h>
#define N 100010
int father[N],link[N];
int find(int x) {
 if(x!=father[x]) {
  int h=father[x];
  father[x]=find(father[x]);
  link[x]=(link[x]+link[h])%2;
 }
 return father[x];
}
void insert(int x,int y) {
 int xx=find(x);
 int yy=find(y);
 father[xx]=yy;
 link[xx]=(link[x]+link[y]+1)%2;
}
int main() {
 int t,n,m,a,b,i,f1,f2;
 char s[3];
 scanf("%d",&t);
 while(t--) {
  scanf("%d%d",&n,&m);
  for(i=1;i<=n;i++)
   father[i]=i;
  memset(link,0,sizeof(link));
  while(m--) { 
   scanf("%s%d%d",s,&a,&b);
   f1=find(a);
   f2=find(b); 
   if(f1==f2) {
    if(s[0]=='A') {
     if(link[a]==link[b])
      printf("In the same gang. ");
     else
       printf("In different gangs. ");
    }

   }
   else {
    if(s[0]=='A')
    printf("Not sure yet. ");
    else
    insert(a,b);
   }
  }
 }
 return 0;
}