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