python函数01

# 没有参数和返回的函数
def say_hi():
    print(" hi!")
say_hi()
say_hi()

# 有参数，无返回值
def print_sum_two(a, b):
    c = a + b
    print(c)

print_sum_two(3, 6)

def hello_some(str):
    print("hello " + str + "!")

hello_some("China")
hello_some("Python")


# 有参数，有返回值
def repeat_str(str, times):
    repeated_strs = str * times
    return repeated_strs


repeated_strings = repeat_str("Happy Birthday!", 4)
print(repeated_strings)


# 全局变量与局部 变量
x = 60

def foo(x):
    print("x is: " + str(x))
    x = 3
    print("change local x to " + str(x))

foo(x)
print('x is still', str(x))

　　输出：

 hi!
 hi!
9
hello China!
hello Python!
Happy Birthday!Happy Birthday!Happy Birthday!Happy Birthday!
x is: 60
change local x to 3
x is still 60