Minimal Change Sequence

You are given three integers a, b, and d. Your task is to calculate the minimum number of steps required to transform a into b. In each step, you are allowed to change the current value by at most d (either increasing or decreasing it).

Mathematically, let \( \Delta = |a - b| \). The minimum number of steps required is given by \[ \lceil \Delta / d \rceil \] which rounds up the division of \(\Delta\) by d.

For example, if a = 5, b = 10 and d = 2, then \(\Delta = 5\) and the answer is \(\lceil 5/2 \rceil = 3\).

inputFormat

The input consists of a single line containing three space-separated integers a, b, and d.

outputFormat

Output a single integer, which is the minimum number of steps required to transform a into b under the constraint that each step can change the value by at most d.

5 10 2

3