Envío 883

Código

def sol(arr , N):

    frontier = []
    result = [None] * N

    for idx in range(N-1, -1, -1):
        
        while(len(frontier) > 0 and arr[idx] >= frontier[-1]):
            _ = frontier.pop()

        cover = -1 if len(frontier) == 0 else frontier[-1]
        
        frontier.append(arr[idx])

        result[idx] = cover

    return result
    

num_cases = int(input())

for i in range(num_cases):

    N = int(input())
    arr = [int(x) for x in input().split()]
    result =  sol(arr, N)
    str_result = ' '.join([str(x) for x in result])
    print(f"Case #{i+1}: {str_result}")