Rotate by 90 degrees [BASIC/IMPORTANT]

Company:Microsoft

Question:

Given an square matrix, turn it by 90 degrees in anti-clockwise direction without using any extra space.

Input:

The first line of input contains a single integer T denoting the number of test cases. Then T test cases follow. Each test case consist of two lines. The first line of each test case consists of an integer N, where N is the size of the square matrix.The second line of each test case contains NxN space separated values of the matrix M.

Output:

Corresponding to each test case, in a new line, print the rotated array.

Constraints:

1 ≤ T ≤ 50
1 ≤ N ≤ 50

Example:

Input
1
3
1 2 3 4 5 6 7 8 9

Output
3 6 9 2 5 8 1 4 7

Code:

import java.util.*;

import java.lang.*;

import java.io.*;

class GFG {

public static void main (String[] args) {

Scanner sc = new Scanner(System.in);

int m =sc.nextInt();

for(int mi=0;mi<m;mi++){

   int n = sc.nextInt();

   int [][]matrix= new int[n][n];

   for(int row=0;row<n;row++){

       for(int col=0;col<n;col++){

           matrix[row][col]=sc.nextInt();

           }

   }

   rotateMatrix(matrix,n);

   displayMatrix(matrix);

        }

}

public static void rotateMatrix(int [][]matrix,int n){

   for(int i=0;i<n/2;i++){

       for(int j=i;j<n-1-i;j++){

           //x(i),xy(i,j),y(j)

           int temp= matrix[i][j];

           matrix[i][j]=matrix[j][n-1-i];

           matrix[j][n-1-i]=matrix[n-1-i][n-1-j];

           matrix[n-1-i][n-1-j]=matrix[n-1-j][i];

           matrix[n-1-j][i]=temp;

       }

   }

}

  public static void displayMatrix(int[][]matrix){ 

   for(int i1=0;i1<matrix.length;i1++){

       for(int j1=0;j1<matrix.length;j1++){

           System.out.print(matrix[i1][j1]+" ");

       }

       

   }

   System.out.println();

}

}

Execution Time: 0.54