# 声明一个无参数函数
def sayHello() :
 print('hello world')
# 运行函数
sayHello()

# 声明一个带参数函数
def printValue(value) :
 print('参数为', value)
# 运行函数
printValue(9527)

# 返回值
# 1. 无返回值
def sum1(a,b):
 sum = a + b

result = sum1(3,8)
print(result)

# 2. 带返回值
def sum2(a,b):
 sum = a + b
 return sum

result = sum2(3,8)
print(result)

# 3. 返回多个值
def sum3(a,b):
 sum1 = a + b
 sum2 = a*b
 return sum1, sum2

result1, result2 = sum3(3,8)
print(result1, result2)

# 可变参数
def sum(*args) :
 print(args)
 result = 0
 for i in args :
 result += i
 return result

print(sum(1))
print(sum(1,2))
print(sum(1,2,3))
 
# 字典
def fun(value1, value2, value3=0, *args, **kwargs):
 print('value1=',value1, 'value2=', value2, 'value3=', value3, 'args=', args, 'kwargs=', kwargs)

fun(1,2)
fun(1,2,3)
fun(1,2,3,4)
fun(value1=4,value2=5,value3=6)
fun(1,2,'hello','world')
fun(1,2,3,name='zhansan',age=23,height=178.3)

# global
a = 10
def fun1():
 #value = a + 1
 global a
 a = a + 1
 # print(a,value)
 print(a)

fun1()

# 递归
# 5! = 5*4*3*2*1 = 5*4! = 5*4*3!=5*4*3*2!=5*4*3*2*1!= 5*4*3*2*1 =
# n! = n*(n-1)!
# fac(n)=n*fac(n-1)
# fac(5) = 5*fac(4) = 5*4*fac(3) = 5*4*3*fac(2) = 5*4*3*2*fac(1) = 5*4*3*2*1
def fac(n):
 # 找出口
 if n==1 or n==0 :
 return 1
 # 进入下一层方式
 return n*fac(n-1)
print(fac(5))

# 匿名函数
add = lambda x,y: x+y
print(add(3,8))

# 习题
import random
def guess(value):
 print('请先想好一个值(1~100):%s,按回车开始游戏'%value)
 input()
 start = 1
 end = 100
 while True:
 pcGuess = random.randint(start,end)
 print('电脑猜%s,用户反馈(1 大了 -1 小了 0 中了) :'%pcGuess)
 result = int(input())
 if result == 1 :
 end = pcGuess - 1
 elif result == -1 :
 start = pcGuess + 1
 else :
 break
# 假设用户想的是78
guess(78)