Practice Arithmetic and Mathematics with the exercise "Execution Circle"

Learning Opportunities

This puzzle can be solved using the following concepts. Practice using these concepts and improve your skills.

Statement

Goal

People are standing in a circle waiting to be executed. Counting begins at a specified point in the circle and proceeds around the circle in a specified direction. starting from S, the next person is executed. The procedure is repeated with the remaining people, starting with the next person alive and going in the same direction, until only one person remains, and is freed.

The problem — given the Number of people , Starting point and Direction — is to choose the position in the initial circle to avoid execution.

example:

N=8
S=5
D=LEFT

5 kills 6

7 kills 8

1 kills 2

3 kills 4

5 kills 7

  1
 X X
X   3
 X X
  5

1 kills 3

  1
 X X
X   X
 X X
  5

5 kills 1

  X
 X X
X   X
 X X
  5

5 is freed

Input

Line 1: Two space-separated long integers indicating the Number of people and the Starting point
Line 2: The word LEFT (clockwise) or RIGHT (counter-clockwise) for the Direction to take

Output

The winning position

Constraints

0<N<10000000000000
0<S<10000000000000

Example

Input

8 5
LEFT

Output

Solve it

A higher resolution is required to access the IDE