代码

#include <bits/stdc++.h>
#define int long long
using namespace std;const int N = 200010, mod = 1e9 + 7;int n, m, k, x, y, z, ans, t;
int w[N], f[N];void solve()
{cin >> m >> n;for (int i = 1; i <= n; i ++ ){cin >> x >> y;for (int j = m; j >= x; j -- ){f[j] = max(f[j], f[j - x] + y);}}cout << f[m] << endl;
}signed main()
{ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);int T = 1;
//	cin >> T;while (T -- ){solve();}
}