a = float(input())
b = float(input())
what = input()
if what == "+":
    print(a + b)
if what == "-":
    print(a - b)
if what == "/" and b != 0:
    print(a/b)
if what == "*":
    print(a*b)
if what == "mod" and b !=0:
    print(a%b)
if what == "pow" and b !=0:
    print(a**b)
if what == "div" and b !=0:
    print(a//b)
else:
    print("Деление на 0!")