Basketball Player

Kozik dreams of becoming a basketball player. After talking with the coach, it turned out that he is too short. Kozik is so determined, however, that he wants to meet the coach's requirement even if it amounts to cheating. So he came up with a brilliant idea: giving himself bumps on the head until he reaches the required height. He noticed that with each hit the bump grows by $m$ cm. Kozik wonders the minimum number of times he will have to hit himself.

The first line of input contains three integers $k$, $w$, $m$ ($1 \le k \le 200$, $1 \le w, m \le 10^9$), denoting respectively Kozik's current height, the height required by the coach, and how much the bump grows after each hit.

The first and only line of output should contain a single integer equal to the minimum number of hits Kozik must perform.