#include<fstream>
using namespace std;
const int N=5001,K=10001;
ifstream in ("rucsac.in");
ofstream out ("rucsac.out");
int g[N],p[N],prf[K],n,k;
int main()
{
	int j,i;
	in>>n>>k;
	for(i=1;i<=n;i++)
		in>>g[i]>>p[i];
	for(j=1;j<=k;j++)
		prf[j]=-1;
	prf[0]=0;
	for(i=1;i<=n;i++)
	{
		for(j=k-g[i];j>=0;j--)
			if(prf[j]!=-1 && prf[j]+p[i]>prf[j+g[i]])
				prf[j+g[i]]=prf[j]+p[i];
	}
	int max=-1;
	for(j=1;j<=k;j++)
		if(prf[j]>max)
			max=prf[j];
	out<<max;
	return 0;
}