Find the direction from given string

Easy
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Microsoft

Problem statement

You are given a string str consisting only of the characters 'L' and 'R'. Imagine a pivot on a compass that is initially pointing North (N).

Your task is to determine the final direction of the pivot after performing a series of rotations as described by the input string.

  • 'L' represents a 90-degree left (counter-clockwise) rotation.


  • 'R' represents a 90-degree right (clockwise) rotation.


    • Detailed explanation ( Input/output format, Notes, Images )
    Input Format: 
    A single line containing the string str.


    Output Format: 
    Print a single character representing the final direction: 'N' for North, 'E' for East, 'S' for South, or 'W' for West.


    Note: 
    The compass directions follow a cycle: North -> East -> South -> West -> North.

This problem can be efficiently solved by mapping the directions to numbers (e.g., N=0, E=1, S=2, W=3) and using modular arithmetic to track the current state.
    Sample Input 1:
    LLRLRRL


    Sample Output 1:
    W


    Explanation for Sample 1:
    - Initial direction: N
- L: -> W
- L: -> S
- R: -> W
- L: -> S
- R: -> W
- R: -> N
- L: -> W
The final direction is West (W).


    Sample Input 2:
    R


    Sample Output 2:
    E


    Explanation for Sample 2:
    - Initial direction: N
- R: -> E
The final direction is East (E).


    Expected Time Complexity:
    The expected time complexity is O(N), where N is the length of the string.


    Constraints:
    0 <= N <= 10^5
`str` contains only 'L' and 'R'.

Time limit: 1 sec
    Approaches (1)
    Find the direction from given string
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    Find the direction from given string
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