如何打印交错字符数组中的单列

def print_single_column(arr):
    rows = len(arr)
    cols = len(arr[0])

    for col in range(cols):
        for row in range(rows):
            if col % 2 == 0:
                print(arr[row][col], end=' ')
            else:
                print(arr[rows - row - 1][col], end=' ')
        print()

# 示例数组
arr = [['A', 'B', 'C', 'D'],
       ['E', 'F', 'G', 'H'],
       ['I', 'J', 'K', 'L'],
       ['M', 'N', 'O', 'P']]

print_single_column(arr)

A E I M 
N J F B 
C G K O 
P L H D