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。
1 #include<cstdio> 2 #include<cstring> 3 #include<iostream> 4 #include<algorithm> 5 using namespace std; 6 const int maxn = 200000; 7 int far[maxn+5]; 8 struct node 9 { 10 int front,rear,length; 11 }lode[maxn+5]; 12 13 int find(int n) 14 { 15 return far[n] == n? n:far[n] = find(far[n]); 16 } 17 bool cmp(node a,node b) 18 { 19 return a.length <= b.length; 20 } 21 int main() 22 { 23 int n,m; 24 while(scanf("%d%d",&n,&m),n||m) 25 { 26 int sum = 0; 27 for(int i = 0; i < m;++i) 28 { 29 scanf("%d%d%d",&lode[i].front,&lode[i].rear,&lode[i].length); 30 sum += lode[i].length; 31 } 32 for(int i = 0;i <= n;++i) //³õʼ»¯²¢²é¼¯ 33 far[i] = i; 34 int tot = 0; 35 sort(lode,lode+m,cmp); 36 for(int i = 0;i < m;++i) 37 { 38 int temp1 = find(lode[i].front); 39 int temp2 = find(lode[i].rear); 40 if(temp1 != temp2) 41 { 42 far[temp1] = temp2; 43 tot += lode[i].length; 44 } 45 } 46 printf("%d ",sum - tot); 47 } 48 return 0; 49 }