import sys

# sys.setrecursionlimit(200005)
# sys.set_int_max_str_digits(200005)
int1 = lambda x: int(x)-1
pDB = lambda *x: print(*x, end="\n", file=sys.stderr)
p2D = lambda x: print(*x, sep="\n", end="\n\n", file=sys.stderr)
def II(): return int(sys.stdin.readline())
def LI(): return list(map(int, sys.stdin.readline().split()))
def LLI(rows_number): return [LI() for _ in range(rows_number)]
def LI1(): return list(map(int1, sys.stdin.readline().split()))
def LLI1(rows_number): return [LI1() for _ in range(rows_number)]
def SI(): return sys.stdin.readline().rstrip()

dij = [(0, 1), (-1, 0), (0, -1), (1, 0)]
# dij = [(0, 1), (-1, 0), (0, -1), (1, 0), (1, 1), (1, -1), (-1, 1), (-1, -1)]
# inf = -1-(-1 << 31)
inf = -1-(-1 << 62)

# md = 10**9+7
md = 998244353

N,W=LI()
vw=LLI(N)
vw.sort(key=lambda x:x[0]/x[1])
lim=min(W,20000000)

dp=[0]*(lim+1)
for v,w in vw[:-1]:
    for i in range(lim-w+1):
        if dp[i]+v>dp[i+w]:dp[i+w]=dp[i]+v

v,w=vw[-1]
ans=0
for i in range(lim+1):
    cur=dp[i]+(W-i)//w*v
    if cur>ans:ans=cur
print(ans)