from itertools import accumulate
n,k=map(int,input().split())
number=list(map(int,input().split()))
for i in range(n):
    number[i]-=k
number1=list(accumulate(number,initial=0))
dict1={}
count=-1
for index,value in enumerate(number1):
    if value not in dict1:
        dict1[value]=index
    else:
        count=max(count,index-dict1[value])
print(count)

先利用accumulate算出前缀和（自己算也行），然后用enumerate函数来枚举数和数的位置，逐步更新区间最大值