Sequence(优先队列)

http://poj.org/problem?id=2442

题意：给你n*m的矩阵，然后每行取一个元素，组成一个包含n个元素的序列，一共有n^m种序列，

让你求出序列和最小的前n个序列的序列和。

#include <stdio.h>
#include <string.h>
#include <vector>
#include <queue>
#include <algorithm>
using namespace std;
const int N=2002;

int main()
{
    int T,m,n,arr1[N],arr2[N];
    priority_queue<int,vector<int>,less<int> >q;
    scanf("%d",&T);
    while(T--)
    {
        scanf("%d%d",&m,&n);
        for (int i = 0; i < n; i ++)
        {
            scanf("%d",&arr1[i]);
        }
        sort(arr1,arr1+n);
        for (int i = 1; i < m; i ++)
        {
            for (int j = 0; j < n; j ++)
            {
                scanf("%d",&arr2[j]);
                q.push(arr1[0]+arr2[j]);
            }
            sort(arr2,arr2+n);
            for (int k = 1; k < n; k ++)
            {
                for (int p = 0; p < n; p ++)
                {
                    if (arr1[k]+arr2[p] > q.top())
                        break;
                    q.pop();
                    q.push(arr1[k]+arr2[p]);
                }
            }
            for (int k = 0; k < n; k ++)
            {
                arr1[n-1-k] = q.top();
                q.pop();
            }
        }
        for (int i = 0; i < n; i ++)
        {
            if (i==n-1)
                printf("%d
",arr1[i]);
            else
                printf("%d ",arr1[i]);
        }
    }
    return 0;
}