m存储前i项和对应下标,a存储前i项和,ans最大长,即求第i项时m[a-k]是否存在
def solve(l, n, k): m = {0:-1} a = ans = 0 for i in range(n): a += l[i] if a not in m.keys(): m[a] = i if a - k in m.keys(): ans = max(ans, i - m[a-k]) return ans while True: try: n, k = map(int, input().split()) l = list(map(int, input().split())) print(solve(l, n, k)) except EOFError: break