a = 21
b = 10
c = 0

c = a + b
print("1，a+b - c 的值为：", c)

c = a - b
print("2 ,a-b - c 的值为：", c)

c = a * b
print("3 ,a*b- c 的值为：", c)

c = a / b
print("4 ,a/b- c 的值为：", c)

c = a % b
print("5 ,a%b- c 的值为：", c)

# 修改变量 a 、b 、c
a = 2
b = 3
c = a ** b
print("6,a**b - c 的值为：", c)  # 2的3次方

a = 10
b = 5
c = a // b
print("7,a//b - c 的值为：", c)  # 除法取整
