import bisect

n, w = map(int, input().split())
a = [int(input()) for _ in range(n)]

prefix_sum = [0] * (n + 1)
for i in range(n):
    prefix_sum[i + 1] = prefix_sum[i] + a[i]

left = 0
last_occurrence = {}
max_length = 0

for right in range(n):
    current = a[right]
    if current in last_occurrence and last_occurrence[current] >= left:
        left = max(left, last_occurrence[current] + 1)
    last_occurrence[current] = right

    target = prefix_sum[right + 1] - w
    k = bisect.bisect_left(prefix_sum, target, left, right + 2)

    if k <= right:
        current_length = right - k + 1
        if current_length > max_length:
            max_length = current_length

print(max_length)