poj 3253 Fence Repair (優先隊列)

poj 3253 Fence Repair (優先隊列)

///優先隊列，每次取兩個最小的木板的長度，再把這個長度放進隊列，反復取
# include 
# include 
# include 
# include 
# include 
# include 
using namespace std;
///長度小的放在前面
class cmp
{
public:
    bool operator ()(const __int64 a,const __int64 b)const
    {
        return a>b;
    }
};
int main()
{
    int n;
    __int64 temp,sum,p1,p2;
    while(~scanf("%d",&n))
    {
        priority_queue<__int64,vector<__int64>,cmp>q;///定義優先隊列
        while(n--)
        {
            scanf("%I64d",&temp);
            q.push(temp);
        }
        sum=0;
        while(q.size()>1)
        {
            p1=q.top();
            q.pop();
            p2=q.top();
            q.pop();
            temp=p1+p2;
            sum+=temp;
            q.push(temp);
        }
        printf("%I64d\n",sum);

    }
    return 0;
}