n, m = map(int, input().split())
ramen = [list(map(int, input().split())) for _ in [0]*n]

dp = [-1] * (m + 1)
dp[0] = 0
for i in range(n):
	ndp = dp[:]
	for j in range(m):
		k = j + ramen[i][0]
		if(dp[j] == -1 or k > m):
			continue
		ndp[k] = max(ndp[k], dp[j] + ramen[i][1])
	dp = ndp[:]
	
print(max(dp))