并查集简单题

(应该是)并查集简单题

HDU1233 还是畅通工程

#include
using namespace std;
#define MAX 100001
int fa[MAX],vis[MAX],ran[MAX];
bool flag;
void ini(){
	for(int i=1; i<=MAX; i++)	{
		fa[i]=i;vis[i]=0;ran[i]=0;
	}
	flag=true;
}
int find(int x)
{
	if (fa[x]!=x)
		fa[x]=find(fa[x]);
	return fa[x];
}
void merge(int x,int y){
	vis[x]=1;
	vis[y]=1;
	int fx=find(x),fy=find(y);
	if(fx!=fy)		fa[fy]=fx;
	else	flag=false;
}
int judge(){
	int sum=0;
	if(flag==true)	{
		for(int i=1; i<=MAX; i++)	{
			int fx=find(i);
			sum+=(vis[fx]==1);
			vis[fx]=0;
		}
		if(sum<=1)	return 1;
	}
	return 0;
}
int main()
{
	int x,y;
	ini();
	while(scanf("%d%d",&x,&y)&&x!=-1&&y!=-1)
	{
		if(x==0&&y==0){
			printf("%s\n",judge()?"Yes":"No");
			ini();
		}
		else{
			if(flag==false)	continue;
			else	merge(x,y);
		}
	}
	return 0;
}

HDU1272 小希的迷宫

只剩主函数了凑合看吧

int main()
{
    int n;
    while(scanf("%d", &n) && n != 0){
        Init(n);
        int len = n * (n - 1) / 2, sum = 0;
        for(int i = 0; i < len; i++) 
        	scanf("%d%d%d", &d[i].u, &d[i].v, &d[i].w);
        sort(d, d + len, cmp);//边权排序 
        for(int i = 0; i < len; i++){
            int fx = Find(d[i].u), fy = Find(d[i].v);
            if(fx != fy){
                fa[fx] = fy;
                sum += d[i].w;
            }
        }
        printf("%d\n", sum);
    }
    return 0;
}