#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;
	for(int i=1;i<=n;i++)
		in>>g[i]>>p[i];
	for(int j=1;j<=k;j++) prf[j]=-1;
	prf[0]=0;
	for(int i=1;i<=n;i++)
	{
		for(int 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(int i=1;i<=k;i++)
		if(prf[i]>max) max=prf[i];
	out<<max;
}