杭电 hdu 1051 Wooden Sticks

贪心问题，不过错了几次，我先将数据按重量进行排序，同时把重量相同的按长度进行排序。然后每处理一个木头，就向后搜索，查找所有可以符合题意的木头。并将已处理的木头进行标记，避免重复查找。

/* THE ROGRAM IS MADE BY PYY *//*----------------------------------------------------------------------------// URL : http://acm.hdu.edu.cn/showproblem.php?pid=1051 Name : Wooden Sticks Date : Wednesday, April 20, 2010 Time Stage : Result:3846516 2011-04-20 23:26:42 Accepted 1051 46MS 344K 2469 B C++ pyyTest Data:Sample Input9942 19 25 48 549 18 26 25 249 28 26 25 2Sample Output221//----------------------------------------------------------------------------*/#include <iostream>#include <stdio.h>#include <string.h>using namespace std;struct node{ int len, wei;};void swap( node & lhs, node & rhs ){ node tmp = lhs; lhs = rhs; rhs = tmp;}node wood[5005];int n, times;int hash[5005];void out(){ int i, j; for( i = 0; i < n; i++ ) printf("(%d, %d) ", wood[i].len, wood[i].wei ); puts("/n");}void psort(){ int i, j, k; int pmin, ipmin; for( i = 0; i < n; i++ ) { ipmin = n - 1; for( j = i; j < n; j++ ) if( wood[j].wei < wood[ipmin].wei || ( wood[j].wei == wood[ipmin].wei && wood[j].len < wood[ipmin].len ) ) ipmin = j; swap( wood[i], wood[ipmin] ); }}void process(){ memset( hash, 0, sizeof( hash ) ); int i, j, k; times = 0; for( i = 0; i < n; i++ ) { if( hash[i] ) continue; ++times; for( j = i + 1, k = i; j < n; j++ ) { if( !hash[j] && wood[k].len <= wood[j].len ) { k = j; hash[j] = 1; } } }}int main( void ){ int i, j, k; int tcase; while( cin >> tcase ) { while( tcase-- ) { cin >> n; for( i = 0; i < n; i++ ) cin >> wood[i].len >> wood[i].wei; psort(); process(); cout << times << endl; } } return 0;}