Poj 2485 highways (prim minimal spanning tree)

For the two points connected by the longest edge in the final generated Minimum Spanning Tree, there is no shorter edge so that the two points are connected in any way.

For this question, the edge length of the longest edge in the Minimum Spanning Tree is the length of the edge connecting the entire graph.

It can be seen that you only need to make a minimum spanning tree to the longest side of the tree that is abstracted by the given city.

#include<bits/stdc++.h>using namespace std;int dist[1020],m[1020][1020];void prim(int n,int dist[],int m[][1020]){    bool p[1020];    for(int i=2;i<=n;i++)    {        p[i]=false;        dist[i]=m[1][i];    }    dist[1]=0,p[1]=true;    for(int i=1;i<=n-1;i++)    {        int min=INT_MAX,k=0;        for(int j=1;j<=n;j++)        {            if(!p[j]&&dist[j]!=0&&dist[j]<min)            {                min=dist[j];                k=j;            }        }        if(k==0)            return;        p[k]=true;        for(int j=1;j<=n;j++)        {            if(!p[j]&&m[k][j]!=0&&(dist[j]==0||dist[j]>m[k][j]))                dist[j]=m[k][j];        }    }}int main(){    int T,N,M;    scanf("%d",&T);    for(int kase=1;kase<=T;kase++)    {        scanf("%d",&N);        for(int i=1;i<=N;i++)            for(int j=1;j<=N;j++)            {                scanf("%d",&M);                m[i][j]=M;            }        prim(N,dist,m);        printf("%d\n",dist[max_element(dist+1,dist+N+1)-dist]);    }    return 0;}