def solve():
    N,I=map(int,input().split())

    inf=float("inf")
    DP=[-inf]*(I+1); DP[0]=0

    for _ in range(N):
        s,a=map(int,input().split())
        for t in range(I,s-1,-1):
            DP[t]=max(DP[t], DP[t-s]+a)
    return max(DP)
#==================================================

print(solve())