CodeWar刷题代码收藏（一）

def tickets(people): till = {100.0:0, 50.0:0, 25.0:0} for paid in people: till[paid] += 1 change = paid-25.0 for bill in (50,25): while (bill <= change and till[bill] > 0): till[bill] -= 1 change -= bill if change != 0: return 'NO' return 'YES'

DNA 序列

import string def DNA_strand(dna): return dna.translate(string.maketrans("ATCG","TAGC")) # Python 3.4 solution || you don't need to import anything :) # return dna.translate(str.maketrans("ATCG","TAGC")) python字符串常见方法

join（）

str="" arr =['abc', 'de', 'dd'] str.join( arr[i] for i in range(len(arr)) )maketrans(  )

创建字符映射的转换表，对于接受两个参数的最简单的调用方式，第一个参数是字符串，表示需要转换的字符，第二个参数也是字符串表示转换的目标。

注：Python3.4已经没有string.maketrans()了，取而代之的是内建函数: bytearray.maketrans()、bytes.maketrans()、str.maketrans()

str1 ="abcde" str2 = "12345" trans = str.maketrans(str1,str2) str ="abbdadef" str.translate(trans)