N,I = map(int,input().split())
SA = [list(map(int,input().split())) for _ in range(N)]
dp = [0] * (I+1)
for s,a in SA:
    for i in reversed(range(I-s+1)):
        dp[i+s] = max(dp[i+s],dp[i] + a)
print(dp[-1])