HDU 2988 Dark roads （裸的最小生成树）

题目链接：http://acm.hdu.edu.cn/showproblem.php?pid=2988

解题报告：一个裸的最小生成树，没看题，只知道结果是用所有道路的总长度减去最小生成树的长度和。

 #include<cstdio>
 #include<cstring>
 #include<iostream>
 #include<algorithm>
 using namespace std;
 const int maxn = ;
 int far[maxn+];
 struct node
 {
     int front,rear,length;
 }lode[maxn+];

 int find(int n)
 {
     return far[n] == n? n:far[n] = find(far[n]);
 }
 bool cmp(node a,node b)
 {
     return a.length <= b.length;
 }
 int main()
 {
     int n,m;
     while(scanf("%d%d",&n,&m),n||m)
     {
         int sum = ;
         for(int i = ; i < m;++i)
         {
             scanf("%d%d%d",&lode[i].front,&lode[i].rear,&lode[i].length);
             sum += lode[i].length;
         }
         for(int i = ;i <= n;++i)  //&sup3;&otilde;&Ecirc;&frac14;&raquo;&macr;&sup2;&cent;&sup2;é&frac14;&macr;
         far[i] = i;
         int tot = ;
         sort(lode,lode+m,cmp);
         for(int i = ;i < m;++i)
         {
             int temp1 = find(lode[i].front);
             int temp2 = find(lode[i].rear);
             if(temp1 != temp2)
             {
                 far[temp1] = temp2;
                 tot += lode[i].length;
             }
         }
         printf("%d\n",sum - tot);
     }
     return ;
 }