poj E

题目链接

#include<iostream>
#include<cstdio>
#include<cstring>
using namespace std;
const int maxn=200000;
int pre[maxn];
int enemy[maxn];

int find(int x)
{
    return pre[x]==x?x:find(pre[x]);
}

void unit(int a,int b)
{
    pre[find(a)]=find(b);
}

int main()
{
    int T;
    scanf("%d",&T);
    while(T--){
        int N,M;
        scanf("%d%d",&N,&M);
        for(int i=1;i<=N;i++){
            pre[i]=i;
        }
        memset(enemy,0,sizeof(enemy));
        char ch;
        int x,y;
        while(M--){
            getchar();
            scanf("%c%d%d",&ch,&x,&y);
            if(ch=='D'){
                if(enemy[x])
                    unit(enemy[x],y);
                if(enemy[y])
                    unit(enemy[y],x);
                enemy[x]=y;
                enemy[y]=x;
            }
            else {
                if(find(x)==find(enemy[y]))
                    printf("In different gangs.\n");
                else if(find(x)==find(y))
                    printf("In the same gang.\n");
                else
                    printf("Not sure yet.\n");
            }
        }
    }
    return 0;
}

/*
#include<iostream>
#include<cstring>
#include<cstdio>
#include<vector>
using namespace std;

int pre[100005];

int find(int x){
    return pre[x]==x?x:find(pre[x]);
}
void join(int x,int y)
{
    int xx=find(x),yy=find(y);
    if(xx!=yy)
        pre[xx]=yy;
}

int main()
{
    int T;
    cin>>T;
    while(T--){
        int N,M;
        cin>>N>>M;
        for(int i=1;i<=N;i++){
            pre[i]=i;
        }
        vector<int> V[100005];
        char ch;
        while(M--){
            getchar();
            cin>>ch;
            if(ch=='A'){
                int x,y;
                scanf("%d%d",&x,&y);
                if(V[x].size()==0&&V[y].size()==0){
                    cout<<"Not sure yet."<<endl;
                    continue;
                }
                int xx=find(x),yy=find(y);
                if(xx==yy){
                    cout<<"In the same gang."<<endl;
                }
                else {
                    cout<<"In different gangs."<<endl;
                }
            }
            else {
                int x,y;
                scanf("%d%d",&x,&y);
                if(V[x].size()>0){
                    join(V[x][0],y);
                }
                V[x].push_back(y);
                if(V[y].size()>0){
                    join(V[y][0],x);
                }
                V[y].push_back(x);
            }
        }
    }
    return 0;
}
*/

#include<stdio.h>

#include<string.h>



#define clear(a,b) memset(a,b,sizeof(a))

#define maxn 200000



int fa[maxn],enemy[maxn];



int getfa(int a)

{

  if (fa[a] == a) return a;

    else fa[a] = getfa(fa[a]);

  return fa[a];

}



int judge(int a,int b)

{

  return getfa(a) == getfa(b);

}



void unite(int a,int b)

{

  fa[getfa(b)] = getfa(a);

}



void work()

{

  int m,n,i,b,a;

  char ch;

  clear(enemy,0);

  scanf("%d%d",&n,&m);

  for(i = 1;i <= n;i++) fa[i] = i;

  for(i = 1;i <= m;i++) {

    getchar();

    scanf("%c%d%d",&ch,&a,&b);

    if (ch == 'D') {

      if (enemy[a]) unite(enemy[a],b);

      if (enemy[b]) unite(enemy[b],a);

      enemy[a] = b;

      enemy[b] = a;

      }

    else {

      if (getfa(a) == getfa(enemy[b])) printf("In different gangs.\n");

      else if (getfa(a) == getfa(b)) printf("In the same gang.\n");

      else printf("Not sure yet.\n");

      }

  }

   return ;

}



int main()

{

  int k;

  scanf("%d",&k);

  while (k--) work();

  return 0;

}