[CCF CSP]最优灌溉201412-4

题目:http://118.190.20.162/view.page?gpid=T18

 

#include <iostream>
#include <algorithm>
#include <algorithm>
using namespace std;
int father[1010];
struct Node{
    int x,y;
    int cost;
}E[100010];
int find(int x){
    return x==father[x]?x:father[x]=find(father[x]);
}
void merge(int x,int y){
    int xx=find(x),yy=find(y);
    if(xx!=yy) {
        father[xx]=yy;
   }
}
bool cmp(Node a,Node b){
    return a.cost<b.cost;
}
int main() {
    for(int i=1;i<=1000;i++){
        father[i]=i;
    }
    int n,m;
    cin>>n>>m;
    for(int i=0;i<m;i++){
        cin>>E[i].x>>E[i].y>>E[i].cost;
    }
    sort(E,E+m,cmp);

    int sum=0;
    for(int i=0;i<m;i++){
        int x=find(E[i].x),y=find(E[i].y);
        if(x!=y){
            merge(E[i].x,E[i].y);
            sum+=E[i].cost;
        }

    }
    cout<<sum<<endl;
    return 0;
}

 

来源：https://blog.csdn.net/Marinebattery/article/details/98861192