完全背包
#include<iostream>
using namespace std;
const int N = 1e4 + 10;
int n,m;
int v[N],w[N],f[N];
int main()
{
cin >> m >> n;
for(int i = 1;i <= n;i ++)
{ cin >> w[i] >> v[i];
for(int j = v[i];j <= m;j ++)
f[j] = max(f[j],f[j-v[i]]+w[i]);
}
cout << f[m];
return 0;
}