#include<fstream.h>

struct gen{int e,k;};
gen a[1002];
int i,n,j,c[1002][1002],w;
ifstream fin("energii.in");
ofstream fout("energii.out");

int main()
{	fin>>n>>w;
	for(i=1;i<=n;i++)
		fin>>a[i].e>>a[i].k;
	for(i=1;i<=n;i++)
		for(j=1;j<=w;j++)
			if(a[i].e<=j&&a[i].k+c[i-1][j-a[i].e]>c[i-1][j])
				c[i][j]=a[i].k+c[i-1][j-a[i].e];
			else	c[i][j]=c[i-1][j];
	fout<<c[n][w];
	return 0;
}