0830Python基础练习

#!/usr/bin/python3
# coding=utf-8

#可以返回多个变量
def look_return():
    a,b = 3,5
    return a,b

c,d = look_return()
print(c, d)

c, d = d, c
print(c, d)

#!/usr/bin/python3
# coding=utf-8

#函数内部对形参直接赋值，不会影响外面的实参变量的值
def demo(num, num_list):
    print("函数内部")

    #赋值语句
    print(‘-‘ * 50)
    print(id(num), id(num_list))
    num = 200
    num_list = [1, 2, 3]
    print(id(num), id(num_list))
    print(num)
    print(num_list)

    print("函数代码完成")

g1_num = 99
g1_list = [4, 5, 6]
print(id(g1_num), id(g1_list))
print(id(g1_num), id(g1_list))
print(g1_num)
print(g1_list)

#!/usr/bin/python3
# coding=utf-8

#num_list传入传出参数
def mutable(num_list):
    num_list += [1, 2, 3]
    print(id(num_list))

g1_list = [6, 7, 8]
print(id(g1_list))
mutable(g1_list)
print(id(g1_list))
print(g1_list)

#!/usr/bin/python3
# coding=utf-8

def demo(num):
    print("函数内部代码")
    print(id(num))
    num += num
    print(id(num))
    print(num)
    print("函数代码完成")

g1_num = 9
print(id(g1_num))
demo(g1_num)
print(g1_num)

#!/usr/bin/python3
# coding=utf-8

#缺省参数方便函数调用时写的短
#缺省参数写到后面
def print_info(name, gender = True):
    gender_text = "男生"
    if not gender:
        gender_text = "女生"

    print("%s 是 %s" %(name, gender_text))

print_info(‘熊大‘, False)

#!/usr/bin/python3
# coding=utf-8

#多个缺省参数就必须带名字
def print_info(name, title="", gender=True):
    """

    :param name: 班上同学的名字
    :param title: 职位
    :param gender: True男生 False女生
    :return:
    """
    gender_text = "男生"

    if not gender:
        gender_text = "女生"

    print("%s%s 是 %s" %(title, name, gender_text))

# 提示：在指定缺省参数的默认值时，应该使用最常见的值作为默认值！
print_info("xiaoming")
print_info("laowang", title="坏人", gender=True)
print_info("xiaomei", gender=False)