a = 6
b = 3
print(a+b)
print(a-b)
print(a*b)
print(a/b)
print(a%b)
print(a//b)#返回商的整数部分，向下取整
print(a**b)
print(a**0.5)
a +=4
print(a)

a -= 3
print(a)

print(3<4 and 5>7)#与
print(3<4 or 5>7)#或
print(not 3>4)#非