6190. 정곤이의 단조 증가하는 수

https://swexpertacademy.com/main/code/problem/problemDetail.do?contestProbId=AWcPjEuKAFgDFAU4 

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def check(a):
    k = str(a)
    for h in range(len(k) - 1):
        if k[h] > k[h + 1]:
            return False
    return True

T = int(input())
for tc in range(1, T + 1):
    N = int(input())
    nums = list(map(int, input().split()))
    result = 0
    for i in range(N - 1):
        for j in range(i + 1, N):
            b = nums[i] * nums[j]
            if check(b):
                result = max(result,b)
        if result == 0:
            result = -1

    print(f'#{tc} {result}')

왜 틀렸는지 잘 모르겠다! 반례를 못 찾았다

T = int(input())
for tc in range(1, T + 1):
    N = int(input())
    nums = list(map(int, input().split()))
    s = []
    for i in range(N - 1):
        for j in range(i + 1, N):
            a = []
            k = str(nums[i] * nums[j])
            n = nums[i] * nums[j]
            if len(k) >= 2:
                for h in range(len(k) - 1):
                    if k[h] <= k[h + 1]:
                        continue
                    else:
                        break
                else:
                    s.append(n)

    if s:
        print(f'#{tc} {max(s)}')
    else:
        print(-1)