#include<fstream>
using namespace std;

int a[5001],p[5001],d[20001],i,j,n,mx,s;

int main()
{
	ifstream f("rucsac.in");
	ofstream g("rucsac.out");
	f >> n >> s;
	for (i=1;i<=n;i++)
		f >> a[i] >> p[i];
	d[0]=1;
	for (i=1;i<=n;i++)
		for (j=s;j>=0;j--)
			if ((d[j]!=0) && (d[j+a[i]]<d[j]+p[i]))
				d[j+a[i]]=d[j]+p[i];
	for (i=0;i<=s;i++)
		if (d[i]>mx)
			mx=d[i];
	g << mx-1;
	return 0;
}