#include<iostream>
#include<cmath>
using namespace std;
const int N = 1010;
int n, m;
int w[N], v[N];
int f[N][N];
int main()
{
cin >> n >> m;
for(int i = 1; i <= n; i ++)
cin >> w[i] >> v[i];
for(int i = 1; i <= n; i ++)
for(int j = 1; j <= m; j ++)
{
//不选i和选i
f[i][j] = f[i - 1][j];
f[i][j] = max(f[i][j], f[i - 1][j - w[i]] + v[i]);
}
cout << f[n][m] << endl;
return 0;
}