#include <bits/stdc++.h>
using namespace std;
int n,m;
struct Thing
{
    int weigh;
    int value;
    
}thing[30001];
int p[30001]={0};
int ok[1001][1001]={0};
int main()
{
    freopen("delicious.in","r",stdin);
    freopen("delicious.out","w",stdout);
    cin>>n>>m;
    int a,b;
    int kinds=0;
    for(int i=1;i<=n;i++)
    {
        cin>>a>>b;
          
            kinds++;
            ok[a][b]=kinds;
            thing[kinds].weigh=a;
            thing[kinds].value=b;
            
        
        
    }
    for(int i=1;i<=kinds;i++)
    {//cout<<thing[i].value<<' '<<thing[i].weigh<<' '<<thing[i].sl<<endl;
        
        
            for(int j=m;j>=thing[i].weigh;j--)
            {
                p[j]=max(p[j],p[j-thing[i].weigh]+thing[i].value);
            }
         
         
    }
    cout<<p[m]<<endl;
    return 0;
}