hdu2818 Building Block

//并查集好题，对并查集有了深入的理解

#include <stdio.h>int father[30005];int num[30005];int lownum[30005];//树某节点下面的节点数int find(int x){int temp;if(x==father[x])return x;temp=find(father[x]);lownum[x]+=lownum[father[x]];return father[x]=temp;}void init(){int i;for(i=0;i<=30002;i++){father[i]=i;num[i]=1;lownum[i]=0;}}int main(){int p,x,y,fx,fy;char ch;init();scanf("%d",&p);while(p--){getchar();scanf("%c",&ch);if(ch=='M'){scanf("%d %d",&x,&y);fx=find(x);fy=find(y);if(fx!=fy){father[fx]=fy;lownum[fx]=num[fy];num[fy]+=num[fx];}elsecontinue;}else{scanf("%d",&x);find(x);printf("%d\n",lownum[x]);}}return 0;}