python学习第八天

floor函数

floor 下取整函数。

import math

math.floor( x )

字符串分割

字符串分割，分割后是列表，默认以空格

def first_word(text: str) -> str:
    """
    returns the first word in a given text.
    """
    aa=text.split(' ')[0]
   
    return aa


if __name__ == "__main__":
    print("Example:")
    print(first_word("Hello world"))

    # These "asserts" are used for self-checking and not for an auto-testing
    assert first_word("Hello world") == "Hello"
    assert first_word("a word") == "a"
    assert first_word("hi") == "hi"
    print("Coding complete? Click 'Check' to earn cool rewards!")

分割。a.split(' ')[0]读取字符串以空格分割的第一个元素。

strip()

去除字符串两边字符，strip（'0'）去除字符串两边的零。

def end_zeros(num: int) -> int:
    b=str(num)
    j=0
    return len(b)-len(b.strip('0'))
   
if __name__ == "__main__":
    print("Example:")
    print(end_zeros(0))

    # These "asserts" are used for self-checking and not for an auto-testing
    assert end_zeros(0) == 1
    assert end_zeros(1) == 0
    assert end_zeros(10) == 1
    assert end_zeros(101) == 0
    assert end_zeros(245) == 0
    assert end_zeros(100100) == 2
    print("Coding complete? Click 'Check' to earn cool rewards!")

列表转化为字符串形式。用join函数。

def solve_it(a):
    '''
    pythontip oj不同于传统oj，代码里面直接使用变量，无需要提前声明，免去复杂的输入解析
    life is short, so i user python~
    you can use variables a
    '''
    b=[]
    for i in a[0::2]:
        b.append(i)
    
    return(''.join(b))  #列表转化为字符串方式
a='12456'
print(solve_it(a))  # 答案需要输出

 列表逆序输出

def solve_it(a):
    '''
    pythontip oj不同于传统oj，代码里面直接使用变量，无需要提前声明，免去复杂的输入解析
    life is short, so i user python~
    '''
    b=[]
    for i in a[::-1]:
        b.append(i)

    return b
a='1234'
print(solve_it(a))  # 答案需要输出