poj 2442 优先队列+多路归并

 1 #include <algorithm>
 2 #include <iostream>
 3 #include <cstring>
 4 #include <cstdio>
 5 #include <queue>
 6 using namespace std;
 7 
 8 const int M = 100;
 9 const int N = 2000;
10 int a[M][N];
11 
12 struct Node
13 {
14     int j, v;
15     Node(){}
16     Node( int _j, int _v )
17     {
18         j = _j, v = _v;
19     }
20     bool operator < ( const Node & o ) const
21     {
22         return v > o.v;
23     }
24 };
25 
26 void merge_list( int * a, int * b, int len )
27 {
28     priority_queue<Node> q;
29     for ( int i = 0; i < len; i++ )
30     {
31         q.push( Node( 0, a[i] + b[0] ) );
32     }
33     for ( int i = 0; i < len; i++ )
34     {
35         Node node = q.top();
36         q.pop();
37         a[i] = node.v;
38         if ( node.j + 1 < len )
39         {
40             q.push( Node( node.j + 1, node.v - b[node.j] + b[node.j + 1] ) );
41         }
42     }
43 }
44 
45 int main ()
46 {
47     int t;
48     scanf("%d", &t);
49     while ( t-- )
50     {
51         int m, n;
52         scanf("%d%d", &m, &n);
53         for ( int i = 0; i < m; i++ )
54         {
55             for ( int j = 0; j < n; j++ )
56             {
57                 scanf("%d", &a[i][j]);
58             }
59             sort( a[i], a[i] + n );
60         }
61         for ( int i = 1; i < m; i++ )
62         {
63             merge_list( a[0], a[i], n );
64         }
65         for ( int i = 0; i < n; i++ )
66         {
67             printf("%d", a[0][i]);
68             if ( i != n - 1 ) putchar(‘ ‘);
69             else putchar(‘\n‘);
70         }
71     }
72     return 0;
73 }