Statement

Given an equation of the form $y=kx+b$ or $y=kx-b$, provide $y, k, b$ and attempt to solve for $x$.

Ensure that the values of $y, k, b$ appearing are all positive integers, and guarantee that the solution $x$ is also an integer.

Input

A string in the format y=kx+b or y=kx-b, where the corresponding mathematical formulas $y=kx+b$ or $y=kx-b$ satisfy $1 \leqslant y,k,b \leqslant 1 \times 10^9$

Output

Output an integer $x$, representing the solution to the equation, ensuring that the result $x$ is always an integer.

Samples

3=1x+0

3

5=6x+5

0

87=15x-3

6