如何测试洗牌程序

import random

#测试次数
test_count = 10000

#记录字典
counter = {}

#测试集合
char_array = [ ‘a‘, ‘b‘, ‘c‘, ‘d‘, ‘e‘, ‘f‘, ‘g‘, ‘h‘, ‘i‘, ‘j‘ ]

#fisher_yates洗牌算法
def fisher_yates_shuffle( array ):
    array_len = len( array )
    for i in range( array_len - 1, -1, -1 ):
        r = random.randrange( 0, array_len )
        array[ i ], array[ r ] = array[ r ], array[ i ]
    return array

#记录每张牌在每个位置出现的次数
def count( array, counter ):
    for i in range( len( char_array ) ):
        char = array[ i ]
        pos = i + 1
        if not counter.get( char ):
            counter[ char ] = {}
        if not counter[ char ].get( pos ):
            counter[ char ][ pos ] = 0
        counter[ char ][ pos ] += 1

#测试test_count次
for i in range( test_count ):
    shuffled = fisher_yates_shuffle( char_array )
    count( shuffled, counter )

#打印结果
for key in sorted( counter.keys() ):
    print( key, counter[ key ] )