poj 3253 Fence Repair (哈夫曼树 优先队列)

题目：http://poj.org/problem?id=3253

没用long long wrong 了一次

#include <iostream>
 #include<cstdio>
 #include<cstring>
 #include<cstdlib>
 #include<stack>
 #include<queue>
 #include<iomanip>
 #include<cmath>
 #include<algorithm>
 #include<map>
 using namespace std;
 
 int main()
 {
     long long n,i,j,a,sum,cnt;//或者 __int64 n,i,j,a,sum,cnt;
     priority_queue<int,vector<int>,greater<int> >pq;
     cin>>n;
     for(i=0; i<n; i++)
     {
         cin>>a;
         pq.push(a);
     }
     sum=0;
     while(!pq.empty())
     {
         cnt=pq.top();
         pq.pop();
         if(pq.empty())
         break;
         cnt+=pq.top();
         sum+=cnt;
         pq.pop();
         pq.push(cnt);
     }
     cout<<sum<<endl;
     return 0;
 }