hdu 2602 Bone Collector

典型的01背包问题，第一个代码是正确的，第二代码错了，一直不明白错在哪儿了？求高手指点！

/* THE PROGRAM IS MADE BY PYY *//*----------------------------------------------------------------------------//Copyright (c) 2011 panyanyany All rights reserved.URL : http://acm.hdu.edu.cn/showproblem.php?pid=2602Name : Bone CollectorDate : Friday，May 6，2011Time Stage : 1 hours aroundResult:006651462011-05-06 01:44:42Accepted100131 MS288 KBVisual C++pyyTest Data:Review://----------------------------------------------------------------------------*/#include <iostream>#include <string.h>using namespace std;const int size = 1010;int tcase, bone, bag;int value[size], weight[size], dp[size];int knapsack(){int i, j, k;memset( dp, 0, sizeof(dp) );for( i = 1; i <= bone; ++i ){for( j = bag; j >= weight[i]; --j )dp[j] = max( dp[j], dp[j-weight[i]] + value[i] );}return dp[bag];}int main(){int i, j, k;while( cin >> tcase ){while( tcase-- ){cin >> bone >> bag;for( i = 1; i <= bone; ++i )cin >> value[i];for( i = 1; i <= bone; ++i )cin >> weight[i];cout << knapsack() << endl;}}return 0;}

 

错误代码

006651402011-05-06 01:20:21Wrong Answer100146 MS4276 KBVisual C++pyy

#include <iostream>#include <string.h>using namespace std;const int size = 1010;int tcase, bone, bag;int value[size], weight[size], dp[size][size];void knapsack(){ int i, j, k; memset( dp, 0, sizeof(dp) ); for( i = 1; i <= bone; ++i ) { for( j = weight[i]; j <= bag; ++j ) dp[i][j] = max( dp[i-1][j], dp[i-1][j-weight[i]] + value[i] ); }}int main(){ int i, j, k; while( cin >> tcase ) { while( tcase-- ) { cin >> bone >> bag; for( i = 1; i <= bone; ++i ) cin >> value[i]; for( i = 1; i <= bone; ++i ) cin >> weight[i]; knapsack(); cout << dp[bone][bag] << endl; } } return 0;}