#include <iostream>

using namespace std;

int main()
{   int n, G, cnst = -1, profit[5000],p[5000], g[5000];
    cin >> n>> G;
    for(int i = 1; i <= n; i++)
         cin >> g[i] >> p[i];
    for(int j = 0; j<=G; j++)
           profit[j] = -1;
    profit[0] = 0;
    for ( int i = 1; i<=G; i++)
       for( int j = G; j>=g[i]; j--)
            if(profit[j-g[i]]!= -1 )
                profit[j] = max(profit[j],profit[j-g[i]]+p[i]);
    cout<< profit[G];
    return 0;
}