# Winner in the Rock-Paper-Scissor game using Bit manipulation

• Difficulty Level : Hard
• Last Updated : 07 Jun, 2022

Two players are playing a series of games of Rock–paper–scissors. There are a total of N games played represented by an array arr[][] where arr[i] is the move of player one and arr[i] is the move of the player two in the ith game from the set {‘R’, ‘P’, ‘S’}. The task is to find the winner of each of the game. Note that the game is a draw if both players choose the same item.
Examples:

Input: arr[] = {“RS”, “SR”, “SP”, “PP”}
Output:

DRAW
Input: arr[] = {“SS”, “RP”, “PS”}
Output:
Draw

Approach: Suppose player one is represented by bit 1 and player two is represented by 0. Moreover, let Rock be represented by 00 (0 in decimal), Paper by 01 (1 in decimal) and Scissors with 10 (2 in decimal).
If player one chooses rock, it will be represented by 100
Similarly, 101 means Paper is chosen by player one.
The first bit indicates the player number and the next two bits for their choice.
Pattern:
100 (4 in decimal) (player 1, rock), 001 (1 in decimal) (player 2, paper) -> player 2 won (4-1 = 3)
101 (5 in decimal) (player 1, paper), 010 (2 in decimal) (player 2, scissors) -> player 2 won (5-2 = 3)
110 (6 in decimal) (player 1, scissors), 000 (0 in decimal) (player 2, rock) -> player 2 won (6-0 = 6)
101 (5 in decimal) (player 1, paper), 000 (0 in decimal) (player 2, rock) -> player 1 won (5-0 = 5)
110 (6 in decimal) (player 1, scissors), 001 (1 in decimal) (player 2, paper) -> player 1 won (6-1 = 5)
100 (4 in decimal) (player 1, rock), 010 (2 in decimal) (player 2, scissors) -> player 1 won (4-2 = 2)
According to the pattern, if the difference is a multiple of 3 then player two wins or if the difference is 4 then the game is a draw. In the rest of the cases, player one wins the game.
Below is the implementation of the above approach:

## C++

 `// C++ implementation of the approach``#include ``using` `namespace` `std;` `// Function to return the``// winner of the game``string winner(string moves)``{``    ``map<``char``, ``int``> data;``    ``data[``'R'``] = 0;``    ``data[``'P'``] = 1;``    ``data[``'S'``] = 2;` `    ``// Both the players chose to``    ``// play the same move``    ``if` `(moves == moves) {``        ``return` `"Draw"``;``    ``}` `    ``// Player A wins the game``    ``if` `(((data[moves] | 1 << (2))``         ``- (data[moves] | 0 << (2)))``        ``% 3) {``        ``return` `"A"``;``    ``}` `    ``return` `"B"``;``}` `// Function to perform the queries``void` `performQueries(string arr[], ``int` `n)``{``    ``for` `(``int` `i = 0; i < n; i++)``        ``cout << winner(arr[i]) << endl;``}` `// Driver code``int` `main()``{``    ``string arr[] = { ``"RS"``, ``"SR"``, ``"SP"``, ``"PP"` `};``    ``int` `n = ``sizeof``(arr) / ``sizeof``(string);` `    ``performQueries(arr, n);` `    ``return` `0;``}`

## Java

 `// Java implementation of the approach``import` `java.util.*;` `class` `GFG``{` `// Function to return the``// winner of the game``static` `String winner(String moves)``{``    ``HashMap data = ``new` `HashMap();``    ``data.put(``'R'``, ``0``);``    ``data.put(``'P'``, ``1``);``    ``data.put(``'S'``, ``2``);` `    ``// Both the players chose to``    ``// play the same move``    ``if` `(moves.charAt(``0``) == moves.charAt(``1``))``    ``{``        ``return` `"Draw"``;``    ``}` `    ``// Player A wins the game``    ``if` `(((data.get(moves.charAt(``0``)) | ``1` `<< (``2``)) -``         ``(data.get(moves.charAt(``1``)) | ``0` `<< (``2``))) % ``3` `!= ``0``)``    ``{``        ``return` `"A"``;``    ``}` `    ``return` `"B"``;``}` `// Function to perform the queries``static` `void` `performQueries(String arr[], ``int` `n)``{``    ``for` `(``int` `i = ``0``; i < n; i++)``        ``System.out.print(winner(arr[i]) + ``"\n"``);``}` `// Driver code``public` `static` `void` `main(String[] args)``{``    ``String arr[] = { ``"RS"``, ``"SR"``, ``"SP"``, ``"PP"` `};``    ``int` `n = arr.length;` `    ``performQueries(arr, n);``}``}` `// This code is contributed by 29AjayKumar`

## Python3

 `# Python3 implementation of the approach` `# Function to return the``# winner of the game``def` `winner(moves):``    ``data ``=` `dict``()``    ``data[``'R'``] ``=` `0``    ``data[``'P'``] ``=` `1``    ``data[``'S'``] ``=` `2` `    ``# Both the players chose to``    ``# play the same move``    ``if` `(moves[``0``] ``=``=` `moves[``1``]):``        ``return` `"Draw"` `    ``# Player A wins the game``    ``if` `(((data[moves[``0``]] | ``1` `<< (``2``)) ``-``         ``(data[moves[``1``]] | ``0` `<< (``2``))) ``%` `3``):``        ``return` `"A"` `    ``return` `"B"` `# Function to perform the queries``def` `performQueries(arr,n):``    ``for` `i ``in` `range``(n):``        ``print``(winner(arr[i]))` `# Driver code``arr ``=` `[``"RS"``, ``"SR"``, ``"SP"``, ``"PP"``]``n ``=` `len``(arr)` `performQueries(arr, n)` `# This code is contributed by Mohit Kumar`

## C#

 `// C# implementation of the approach``using` `System;``using` `System.Collections.Generic;` `class` `GFG``{` `// Function to return the``// winner of the game``static` `String winner(String moves)``{``    ``Dictionary<``char``,``               ``int``> data = ``new` `Dictionary<``char``,``                                          ``int``>();``    ``data.Add(``'R'``, 0);``    ``data.Add(``'P'``, 1);``    ``data.Add(``'S'``, 2);` `    ``// Both the players chose to``    ``// play the same move``    ``if` `(moves == moves)``    ``{``        ``return` `"Draw"``;``    ``}` `    ``// Player A wins the game``    ``if` `(((data[moves] | 1 << (2)) -``         ``(data[moves] | 0 << (2))) % 3 != 0)``    ``{``        ``return` `"A"``;``    ``}` `    ``return` `"B"``;``}` `// Function to perform the queries``static` `void` `performQueries(String []arr, ``int` `n)``{``    ``for` `(``int` `i = 0; i < n; i++)``        ``Console.Write(winner(arr[i]) + ``"\n"``);``}` `// Driver code``public` `static` `void` `Main(String[] args)``{``    ``String []arr = { ``"RS"``, ``"SR"``, ``"SP"``, ``"PP"` `};``    ``int` `n = arr.Length;` `    ``performQueries(arr, n);``}``}` `// This code is contributed by 29AjayKumar`

## Javascript

 ``

Output:

```A
B
A
Draw```

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