poj1258

依旧是最小生成树的基础题~

#include<iostream>
#include<algorithm>
using namespace std;
int father[101];
struct n1
{
	int s,e,w;
};
n1 path[6000];
bool cmp(n1 a,n1 b)
{
	return a.w<b.w;
}
int find(int i)
{
	while(father[i]!=i)
	{
		i=father[i];
	}
	return i;
}
int kruskal(int v,int e)
{
	int temp1,temp2,i,sum,num_bian;
	for(i=1;i<=v;i++)
	{
		father[i]=i;
	}
	sort(path+1,path+e+1,cmp);
	i=sum=num_bian=0;
	v--;
	while(num_bian!=v)
	{
		i++;
		temp1=find(path[i].s);
		temp2=find(path[i].e);
		if(temp1!=temp2)
		{
			sum+=path[i].w;
			num_bian++;
			if(temp1>temp2)
			{
				temp1^=temp2^=temp1^=temp2;
			}
			father[temp2]=temp1;
		}
	}
	return sum;
}
int main()
{
		int t,i,j,k,map[101][101],n;
		while(scanf("%d",&n)!=EOF){

		k=0;
		for(i=1;i<=n;i++)
		for(j=1;j<=n;j++)
		{
			scanf("%d",&map[i][j]);
			if(j>i)
			{
				k++;
				path[k].s=i;
				path[k].e=j;
				path[k].w=map[i][j];
			}
		}
		printf("%d\n",kruskal(n,k));
	}
}

poj1258