The CCF (data center): Minimum Spanning Tree Algorithm + kruskal

data center

201812-4

Here is the application of the minimum spanning tree

#include<iostream>
#include<cstdio>
#include<algorithm>
#include<cstring>
#include<string>
using namespace std;
const int maxn=50004;
const int maxm=100005;
int n,m,root;
struct node{
    int from;
    int to;
    int w;
    bool operator<(const node& t)const{
        return w<t.w;
    }
};
node edge[maxm];
int set[maxn];
int find(int x){
    return x==set[x]?set[x]:set[x]=find(set[x]);
}
int kruskal(){
    for(int i=0;i<=n;i++){
        set[i]=i;
    }
    int ans=0;
    for(int j=0;j<m;j++){
        int x=edge[j].from;
        int y=edge[j].to;
        int w=edge[j].w;
        x=find(x),y=find(y);
        if(x!=y){
            set[x]=y;
            ans++;
            if(ans==n-1){
                return w;
            }
        }
    }
}
int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    cin>>n>>m>>root;
    for(int i=0;i<m;i++){
        cin>>edge[i].from>>edge[i].to>>edge[i].w;
    }
    sort(edge,edge+m);
    cout<<kruskal()<<endl;
    //system("pause");
    return 0;
}