from collections import *

N, W = map(int, input().split())
Q = deque()
D = defaultdict(int)
ans = 0
S = 0
for i in range(N):
    A = int(input())
    D[A] += 1
    S += A
    Q.append(A)
    while D[A] == 2 or S > W:
        B = Q.popleft()
        D[B] -= 1
        S -= B
    ans = max(ans, len(Q))
print(ans)