Windra has just won gold in the Olympic pole vault, and in the rush of excitement they leave the stadium still carrying their pole. Then they hear that their long-lost brother Bindra is waiting somewhere in the Olympic village. Windra starts at point ~a~, Bindra is at point ~b~, and every point in the village is represented by an integer on a number line.

Windra can move in two ways:

• For every integer ~x~, they may walk between points ~x~ and ~x+1~.
• For every integer ~x~, there are vault pads at points ~kx~ and ~k(x+1)~, and Windra may use the pole to launch between these two points.

Each walk or vault takes exactly one minute.

Given ~k~, ~a~, and ~b~, find the minimum number of minutes Windra needs to reach Bindra.

Input

The only line contains three integers ~k~, ~a~, and ~b~ (~1 \leq k \leq 10^9~, ~-10^9 \leq a, b \leq 10^9~), in this order.

Output

Print one integer: the minimum number of minutes needed to get from point ~a~ to point ~b~.

Example 1

Input

4 1 10

Output

5

Explanation

In the sample, one optimal route is:

$$\displaystyle 1 \to 0 \to 4 \to 8 \to 9 \to 10. $$