#include<stdio.h>
int max(int a, int b)
{
	if (a > b)
		return a;
	else
		return b;
}
int s[1003], a[1003];
int dp[1003];
int main()
{
	int n, I;
	scanf("%d %d", &n, &I);
	int i, j;
	for (i = 0; i < n; i++)
		scanf("%d %d", &s[i], &a[i]);
	for (i = 0; i <= I; i++)
		dp[i] = -1;
	dp[0] = 0;
	for (i = 0; i < n; i++)
	{
		for (j = I - s[i]; j >= 0; j--)
		{
			if (dp[j] < 0)
				continue;
			dp[j + s[i]] = max(dp[j + s[i]], dp[j] + a[i]);
		}
	}
	int ans = 0;
	for (i = 0; i <= I; i++)
		ans = max(ans, dp[i]);
	printf("%d\n", ans);
	return 0;
}