T1267-01背包问题
时间限制: 1Sec 内存限制: 128MB 提交: 759 解决: 294

样例输入

10 4
2 1
3 3
4 5
7 9

样例输出

12

解法一：

#include<iostream>
#include <cstdio>
//0/1 背包问题
using namespace std;
int dp[35][205];
int w[35];
int c[205];
int main() {
	int m, n;
	cin >> m >> n;
	for (int i = 1;i <= n;i++) {
		cin >> w[i] >> c[i];
	}
	for (int i = 1;i <= n;i++) {
		for (int j = 1;j <= m;j++) {
			if (j < w[i])
				dp[i][j] = dp[i - 1][j];
			else
				dp[i][j] = max(dp[i - 1][j], dp[i - 1][j - w[i]] + c[i]);
		}
	}
	cout << dp[n][m];
	return 0;
}

解法二：更优

#include <iostream>
using namespace std;
int dp[205];
int w[35];
int c[205];
int main(){
	int m, n;
	cin >> m >> n;
	for (int i = 1;i <= n;i++) {
		cin >> w[i] >> c[i];
	}
	for (int i = 1;i <= n;i++) {
		for (int j = m;j >= 1;j--) {//递归从后面开始
			if (j >= w[i])
				dp[j] = max(dp[j], dp[j - w[i]] + c[i]);
		}
	}
	cout << dp[m];
	return 0;
}