#include <iostream>
#include <cstdio>
using namespace std;
const int maxN = 3e4 + 10;

struct fruit{
	int size;
	int value;
	int ans;
}a[maxN];

int m, n;
int main(void){
	freopen("delicious.in", "r", stdin);
	freopen("delicious.out", "w", stdout);
	scanf("%d%d", &n, &m);
	for (int i = 1; i <= n; i ++){
		scanf("%d%d", &a[i].size, &a[i].value);
	}
	for (int i = 1; i <= n; i ++)
		for (int j = m; j >= a[i].size; j --)
			a[j].ans = a[j].ans > (a[j - a[i].size].ans + a[i].value) ? a[j].ans : (a[j - a[i].size].ans + a[i].value);
	printf("%d", a[m].ans);
	return 0;
}