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=2602 Name : Bone Collector Date : Friday，May 6，2011 Time Stage : 1 hours around Result: 00665146 2011-05-06 01:44:42 Accepted 1001 31 MS 288 KB Visual C++ pyy Test 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

00665140

2011-05-06 01:20:21

Wrong Answer

1001

46 MS

4276 KB

Visual 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; }