Rotate by 90 degree

PROBLEM :

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

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SIMPLE c++ IMPLEMENTATION :
--------------------------------------------------------------------------------

#include<iostream>
using namespace std;
#define MAX 50
void rotate_90deg(int [MAX][MAX],int ) ;
int main()
 {
int t,no,mat[MAX][MAX] ;
int i,j ;
cin>>t ;
while(t--)
{
   cin>>no ;
 
   for(i=0;i<no;i++)
       for(j=0;j<no;j++)
           cin>>mat[i][j] ;
         
   rotate_90deg(mat,no) ;
 
   for(i=0;i<no;i++)
       for(j=0;j<no;j++)
           cout<<mat[i][j]<<" " ;
         
   cout<<endl ;
}
return 0;
}

void rotate_90deg(int mat[MAX][MAX],int no)
{
    int i,j ;
    int m[no][no] ;
   
    for(i=0;i<no;i++)
        for(j=0;j<no;j++)
            m[i][j]=mat[j][no-1-i] ;
           
    for(i=0;i<no;i++)
        for(j=0;j<no;j++)
            mat[i][j]=m[i][j] ;
}

--------------------------------------------------------------------------------
SIMPLE c++ IMPLEMENTATION :(without using any extra space)
--------------------------------------------------------------------------------

#include<iostream>
using namespace std;
#define MAX 50
void rotate_90deg(int [MAX][MAX],int ) ;
int main()
 {
int t,no,mat[MAX][MAX] ;
int i,j ;
cin>>t ;
while(t--)
{
   cin>>no ;
 
   for(i=0;i<no;i++)
       for(j=0;j<no;j++)
           cin>>mat[i][j] ;
         
   rotate_90deg(mat,no) ;
 
   for(i=0;i<no;i++)
       for(j=0;j<no;j++)
           cout<<mat[i][j]<<" " ;
         
   cout<<endl ;
}
return 0;
}

void rotate_90deg(int mat[MAX][MAX],int no)
{
    int i,j ;
    int temp ;
   
    for(i=0;i<no/2;i++)
    {
        for(j=i;j<no-i-1;j++)
        {
            temp=mat[i][j] ;
            mat[i][j]=mat[j][no-i-1] ;
            mat[j][no-i-1]=mat[no-i-1][no-j-1] ;
            mat[no-i-1][no-j-1]=mat[no-j-1][i] ;
            mat[no-j-1][i]=temp ;
        }
    }
}

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