hdu 1162 Eddy's picture

最小生成树裸题，没有初始化都能AC，看来测试数据只有一组

#include<iostream>
#include<vector>
#include<cmath>
#include<cstdio> 
#define inf 1<<30
#define maxn 105
using namespace std;
struct stu
{
	double x,y;
};
stu mapp[maxn];
int n; 
vector<int>root[maxn];
double vaule[maxn][maxn];
int visit[maxn];
void prim()
{
	double d[maxn];
	fill(d,d+maxn,inf);
	fill(visit,visit+maxn,0);
	double re=0;
	d[0]=0;
	while(1)
	{
		int v=-1;
		for(int i=0;i<n;i++)
		{
			if(!visit[i]&&(v==-1||d[i]<d[v])) v=i;
		}
		if(v==-1) break;
		re+=sqrt(d[v]);
		visit[v]=1;
		for(int i=0;i<root[v].size();i++)
		{
			int x=root[v][i];
			d[x]=min(d[x],vaule[v][x]);
		}
	}
	printf("%.2lf\n",re);
}
int main()
{

	while(cin>>n)
	{
		for(int i=0;i<maxn;i++) root[i].clear();
		for(int i=0;i<n;i++)
		{
			cin>>mapp[i].x>>mapp[i].y;
			for(int j=0;j<i;j++)
			{
				int l=pow(mapp[i].x-mapp[j].x,2)+pow(mapp[i].y-mapp[j].y,2);
				root[i].push_back(j);
				root[j].push_back(i);
				vaule[i][j]=l;
				vaule[j][i]=l;
			}
			
		}
		prim();
	}
	return 0;
}

hdu 1162 Eddy's picture

原文：http://blog.csdn.net/zafkiel_nightmare/article/details/47989909