s = str(input())
stack = []
for c in s:
    if not stack:
        stack.append(c)
    else:
        if c != '*' and c != '+':
            if stack[-1] != '*' and stack[-1] != '+':
                stack[-1] += c
            elif stack[-1] == '*':
                stack.pop()
                x = stack.pop()
                stack.append(str(int(x)+int(c)))
            else:
                stack.pop()
                x = stack.pop()
                stack.append(str(int(x)*int(c)))
        else:
            stack.append(c)
print(*stack)