局部变量和全局变量

n, s = 10, 100
def fact(n):
  global s
  for i in range(1, n+1)
    s *= i
  return s #全局变量s
print(fact(n), s)

fact()函数中使用global保留字声明此处s是全局变量s

局部变量为组合数据类型且未创建，等同于全局变量

ls = ["F", "f"]
def func(a):
  ls.append(a)
  return
func("C")
print(ls)

ls = ["F", "f"]
def func(a):
  ls = [ ]
  ls.append(a)
  return
func("C")
print(ls)