"""

https://yukicoder.me/problems/no/3401

1e6までdpできるか


"""

N,W = map(int,input().split())

INF = float("inf")
dp = [-INF] * (10**6+1)
dp[0] = 0


for i in range(N):
    v,w = map(int,input().split())
    for i in range(len(dp)-w):
        dp[i+w] = max(dp[i+w],dp[i] + v)

for i in range(len(dp)-1):
    dp[i+1] = max(dp[i+1],dp[i])

ans = 0
for i in range(1,len(dp)):
    ans = max( ans , (W//i)*dp[i] + dp[W%i] )

print (ans)