#include <cstdio>
using namespace std;
FILE *f, *g;
int ma,i,j,k,n,ep[5001],c[5001],b[5001];
int main()
{f=fopen ("energii.in","r");
g=fopen ("energii.out","w");
fscanf (f,"%d%d",&n,&k);
for (i=1;i<=n;++i)
fscanf (f,"%d%d",&ep[i],&c[i]);
b[ep[1]]=c[1];
for (i=2;i<=n;++i)
{for (j=k;j>=1;--j)
if (b[j])
if (b[j+ep[i]]<b[j]+c[i])
b[j+ep[i]]=b[j]+c[i];
if (b[ep[i]]<c[i])
b[ep[i]]=c[i];
}
ma=0;
for (i=k;i>=1;--i)
if (b[i]>ma)
ma=b[i];
fprintf (g,"%d\n",ma);
return 0;
}