in1t

def snake(n):
    arr = [[0 for x in range(n)] for y in range(n)]
    index = 0
    x = -1
    y = 0
    sign = 1
    while n > 0:
        for _ in range(n):
            x += sign
            index += 1
            arr[y][x] = index
        n -= 1
        for _ in range(n):
            y += sign
            index += 1
            arr[y][x] = index
        sign *= -1
    return arr

def ziggurat(n):
    lst = list(range(1, n + 1)) + list(range(n - 1, 0, -1))
    return [[min(x, y) for x in lst] for y in lst]

def pprint(arr):
    for row in arr:
        print(' '.join((str(i) for i in row)))

if __name__ == '__main__':
    pprint(snake(5))
    pprint(ziggurat(3))