PKU1861Kruskal算法

#include <stdio.h>
#include <stdlib.h>
#include <malloc.h>
#include <limits.h>
#include <ctype.h>
#include <math.h>
#include <string.h>
#include <string>
#include <algorithm>
#include <iostream>
#include <set>
#include <stack>
#include <queue>
#include <vector>
#include <deque>
using namespace std;
#define N 1005
int father
;
struct node{
int x;
int y;
int len;
}map[15111];
int m,n;

struct node1{
int xx;
int yy;
}map1[15111];
bool cmp(node a,node b){
return a.len < b.len;
}

int find(int x){
int r = x;
while(father[r] != r){
r = father[r];
}
int i=x,k;
while(i != r){
k = father[r];
father[i] = r;
i = k;
}

return r;
}

int main(){
int i;

while(~scanf("%d%d",&n,&m)){

for(i=0;i<m;i++){
scanf("%d%d%d",&map[i].x,&map[i].y,&map[i].len);
}
sort(map,map+m,cmp);
memset(father,0,sizeof(father));
for(i=1;i<=n;i++){
father[i] = i;
}
int ans=0;
int max = -1000;
int count = 0;
for(i=0;i<m;i++){
int f1 = find(father[map[i].x]);
int f2 = find(father[map[i].y]);
if(f1 != f2){
father[f1] = f2;
ans+=map[i].len;
if(map[i].len > max){
max = map[i].len;
}
map1[count].xx = map[i].x;
map1[count].yy = map[i].y;
count++;
}
}
printf("%d\n",max);
printf("%d\n",count);
for(i=0;i<count;i++){
printf("%d %d\n",map1[i].xx,map1[i].yy);
}
}

return 0;
}