#include <cstdio>
#include<algorithm>
using namespace std;
int d[10005];
int main()
{
    freopen("rucsac.in","r",stdin);
    freopen("rucsac.out","w",stdout);
    int n,i,gmax,last=0,max=0,j,g,p;
    scanf("%d%d",&n,&gmax);
    for(i=1;i<=n;i++)
        d[i]=-1;
    d[0]=0;
    for(i=1;i<=n;i++)
    {
        scanf("%d%d",&g,&p);
        for(j=last;j>=0;j--)
        {
            if(j+g>gmax)
                continue;
            if(d[j]!=-1)
                {
                    if(d[j+g]<d[j]+p)
                    {
                        d[j+g]=d[j]+p;
                        if(last<g+j)
                            last=g+j;
                        if(d[j+g]>d[max])
                            max=j+g;
                    }
                }
        }
    }
    printf("%d",d[max]);
}