洛谷-P2871 [USACO07DEC]Charm Bracelet S

洛谷-P2871 [USACO07DEC]Charm Bracelet S

原题链接：

• 题目描述
• 输入格式
• 输出格式
• 输入输出样例
• C++代码

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题目描述

Bessie has gone to the mall's jewelry store and spies a charm bracelet. Of course, she'd like to fill it with the best charms possible from the N (1 ≤ N ≤ 3,402) available charms. Each charm i in the supplied list has a weight Wi (1 ≤ Wi ≤ 400), a 'desirability' factor Di (1 ≤ Di ≤ 100), and can be used at most once. Bessie can only support a charm bracelet whose weight is no more than M (1 ≤ M ≤ 12,880).

Given that weight limit as a constraint and a list of the charms with their weights and desirability rating, deduce the maximum possible sum of ratings.

有N件物品和一个容量为V的背包。第i件物品的重量是c[i]，价值是w[i]。求解将哪些物品装入背包可使这些物品的重量总和不超过背包容量，且价值总和最大。

输入格式

* Line 1: Two space-separated integers: N and M

* Lines 2..N+1: Line i+1 describes charm i with two space-separated integers: Wi and Di

第一行：物品个数N和背包大小M

第二行至第N+1行：第i个物品的重量C[i]和价值W[i]

输出格式

* Line 1: A single integer that is the greatest sum of charm desirabilities that can be achieved given the weight constraints

输出一行最大价值。

输入输出样例

输入 #1

4 6
1 4
2 6
3 12
2 7

输出 #1

23

C++代码

#include <iostream>
using namespace std;

int f[12885];

int main() {
    int n, m;
    cin >> n >> m;
    int c[n], w[n];
    for (int i=0; i<n; ++i)
        cin >> c[i] >> w[i];
    for (int i=0; i<n; ++i)
        for (int j=m; j>=c[i]; --j)
            f[j] = max(f[j], f[j-c[i]]+w[i]);
    cout << f[m] << endl;
    return 0;
}