hdu1232

强连通分量计数

#include<stdlib.h>
#include<string.h>
#include<stdio.h>
int root[1010];
int n,m;
int findroot(int index){
	if(root[index] == -1)
		return index;
	else
		return findroot(root[index]);
}
int main(){
	int i;
	int j;
	int bufx,bufy;
	freopen("in_kruskal.txt","r",stdin);
	freopen("out.txt","w",stdout);
	while(scanf("%d",&n) && n != 0){
		scanf("%d",&m);
		memset(root,-1,sizeof(root));
		while(m--){
			scanf("%d %d",&bufx,&bufy);
			int bufroot1 = findroot(bufx-1);
			int bufroot2 = findroot(bufy-1);
			if(bufroot1 != bufroot2)
				root[bufroot1] = bufroot2;
		}
		int count = 0;
		for(i = 0 ; i < n ; i++){
			if(root[i] == -1)
				count++;
		}
		printf("%d\n",count-1);
	}
	return 0;
}