def main() :
    lst = input().split()
    stack = []
    for i in lst :
        if i == "+" :
            x = stack.pop()
            y = stack.pop()
            stack.append(x + y)

        elif i == "-" :
            x = stack.pop()
            y = stack.pop()
            stack.append(y - x)

        elif i == "*" :
            x = stack.pop()
            y = stack.pop()
            stack.append(x * y)

        else :
            stack.append(int(i))

    print(stack.pop())


if __name__ == "__main__" :
    main() def main() :
    lst = input().split()
    stack = []
    for i in lst :
        if i == "+" :
            x = stack.pop()
            y = stack.pop()
            stack.append(x + y)

        elif i == "-" :
            x = stack.pop()
            y = stack.pop()
            stack.append(y - x)

        elif i == "*" :
            x = stack.pop()
            y = stack.pop()
            stack.append(x * y)

        else :
            stack.append(int(i))

    print(stack.pop()) main lst = input().split() lst input().split() ().split () input split stack = [] stack [] for i in lst :
        if i == "+" :
            x = stack.pop()
            y = stack.pop()
            stack.append(x + y)

        elif i == "-" :
            x = stack.pop()
            y = stack.pop()
            stack.append(y - x)

        elif i == "*" :
            x = stack.pop()
            y = stack.pop()
            stack.append(x * y)

        else :
            stack.append(int(i))

     i lst if i == "+" :
            x = stack.pop()
            y = stack.pop()
            stack.append(x + y)

        elif i == "-" :
            x = stack.pop()
            y = stack.pop()
            stack.append(y - x)

        elif i == "*" :
            x = stack.pop()
            y = stack.pop()
            stack.append(x * y)

        else :
            stack.append(int(i))

     i == "+" i "+" x = stack.pop() x stack.pop() stack.pop stack pop y = stack.pop() y stack.pop() stack.pop stack pop stack.append(x + y) stack.append stack append x + y x y elif i == "-" :
            x = stack.pop()
            y = stack.pop()
            stack.append(y - x)

         i == "-" i "-" x = stack.pop() x stack.pop() stack.pop stack pop y = stack.pop() y stack.pop() stack.pop stack pop stack.append(y - x) stack.append stack append y - x y x elif i == "*" :
            x = stack.pop()
            y = stack.pop()
            stack.append(x * y)

         i == "*" i "*" x = stack.pop() x stack.pop() stack.pop stack pop y = stack.pop() y stack.pop() stack.pop stack pop stack.append(x * y) stack.append stack append x * y x y stack.append(int(i)) stack.append stack append int(i) int i print(stack.pop()) print stack.pop() stack.pop stack pop if __name__ == "__main__" :
    main() __name__ == "__main__" __name__ "__main__" main() main def main() :
    lst = input().split()
    stack = []
    for i in lst :
        if i == "+" :
            x = stack.pop()
            y = stack.pop()
            stack.append(x + y)

        elif i == "-" :
            x = stack.pop()
            y = stack.pop()
            stack.append(y - x)

        elif i == "*" :
            x = stack.pop()
            y = stack.pop()
            stack.append(x * y)

        else :
            stack.append(int(i))

    print(stack.pop()) def main() :
    lst = input().split()
    stack = []
    for i in lst :
        if i == "+" :
            x = stack.pop()
            y = stack.pop()
            stack.append(x + y)

        elif i == "-" :
            x = stack.pop()
            y = stack.pop()
            stack.append(y - x)

        elif i == "*" :
            x = stack.pop()
            y = stack.pop()
            stack.append(x * y)

        else :
            stack.append(int(i))

    print(stack.pop()) main
def main() :
    lst = input().split()
    stack = []
    for i in lst :
        if i == "+" :
            x = stack.pop()
            y = stack.pop()
            stack.append(x + y)

        elif i == "-" :
            x = stack.pop()
            y = stack.pop()
            stack.append(y - x)

        elif i == "*" :
            x = stack.pop()
            y = stack.pop()
            stack.append(x * y)

        else :
            stack.append(int(i))

    print(stack.pop())


if __name__ == "__main__" :
    main()