N,I=map(int,input().split())
inf=1<<60
dp=[-inf]*(I+1)
dp[0]=0
for i in range(N):
    s,a=map(int,input().split())
    for i in range(I,s-1,-1):
        dp[i]=max(dp[i],dp[i-s]+a)
ans=max(dp)
print(ans)