200220906刷题
第一个很简单， 第二个评论区有人用求余公式，学到了
https://leetcode.cn/problems/zuo-xuan-zhuan-zi-fu-chuan-lcof/solution/mian-shi-ti-58-ii-zuo-xuan-zhuan-zi-fu-chuan-qie-p/
s = ['a','b','c','d','e','f','g','h','i','j']
k = 2
for i in range(k, k + len(s)):
print('{0} , {1} , {2}'.format(i , i % len(s),s[i % len(s)]))