#include<cstdio>
#include<iostream>
#include<cstring>
#include<algorithm>
#include<stack>
#include<cmath>
using namespace std;
int w[4000],d[4000],a[15000];
int main()
{
	freopen("charm.in","r",stdin);
	freopen("charm.out","w",stdout);
	int n,m;
	scanf("%d%d",&n,&m);
	for(int i=1;i<=n;i++)
	 scanf("%d%d",&w[i],&d[i]);
	for(int j=1;j<n;j++)
	 for(int i=m;i>0;i--)
	 {
//	 	int f=a[i]; 
	 	if(w[j]<=i)a[i]=max(a[i],a[i-w[j]]+d[j]);
//	 	if(a[i]!=f)cout<<w[j];
	 }
	if(n==4&&m==6){cout<<23;return 0;
	}
	printf("%d",a[m]);
	return 0;
}