def test():

    #算术运算符
    a = 21
    b = 10
    c = 0
    
    c = a + b
    print("1 - c 的值为：")
    print(c)
    
    c = a - b
    print("2 - c 的值为：") 
    print(c) 
    
    c = a * b
    print("3 - c 的值为：")
    print(c) 
    
    c = a / b
    print("4 - c 的值为：")
    print(c) 
    
    c = a % b
    print("5 - c 的值为：")
    print(c)
    
    # 修改变量 a 、b 、c
    a = 2
    b = 3
    c = a**b 
    print("6 - c 的值为：")
    print(c)
    
    a = 10
    b = 5
    c = a//b 
    print ("7 - c 的值为：")
    print(c)



    #比较运算符
    a = 21
    b = 10
    c = 0
    if  a == b :
        print ("1 - a 等于 b")
    else:
        print("1 - a 不等于 b")