题解 | #最小邮票数#

#include <iostream>
#include<algorithm>
#include<vector>
using namespace std;

int main() {
    int number;
    while (cin >> number) { // 注意 while 处理多个 case
        int n;
        cin >> n;
        vector<int> weights(n);
        for (int i = 0; i < n; i++) {
            cin >> weights[i];
        }
        vector<int> dp(number + 1, n + 1);
        dp[0] = 0;
        for (int i = 0; i < n; i++) {
            for (int j = number; j >= weights[i]; j--) {
                dp[j] = min(dp[j], dp[j - weights[i]] + 1);
            }
        }
        if (dp[number] == n + 1)
            cout << 0 << endl;
        else
            cout << dp[number] << endl;
    }
}
// 64 位输出请用 printf("%lld")