This is the most asked question from matrix in the interviews . We will see how we can do this rotation in java and C++ .
Input : { { 1 , 2 } , { 3 , 4 } }
Output : { { 2 , 4 } , { 1 , 3 } }
We have implemented the code in two languages , Java and C++
Java Code :
public class Matrix
{
public static void rotate90(int[][] mat)
{
for(int i=0;i<mat.length;i++)
{
for(int j=i+1;j<mat[i].length;j++)
{
int temp = mat[i][j];
mat[i][j] = mat[j][i];
mat[j][i]= temp;
}
}
for(int i=0;i<mat.length;i++)
{
int low=0;
int high= mat.length-1;
while(low<high)
{
int temp = mat[low][i];
mat[low][i] = mat[high][i];
mat[high][i]= temp;
low++;
high--;
}
}
}
public static void main(String [] args)
{
int [][] mat = { {1,2,3},{3,4,5},{7,2,0}};
rotate90(mat);
}
}
C++ Code :
#include<iostream>
public class Matrix
{
public static void rotate90(int[][] mat, int n)
{
for(int i=0;i<n;i++)
{
for(int j=i+1;j<n;j++)
{
int temp = mat[i][j];
mat[i][j] = mat[j][i];
mat[j][i]= temp;
}
}
for(int i=0;i<n;i++)
{
int low=0;
int high= n-1;
while(low<high)
{
int temp = mat[low][i];
mat[low][i] = mat[high][i];
mat[high][i]= temp;
low++;
high--;
}
}
}
}
int main()
{
int [][] mat = {{1,2},{3,4}};
Matrix.rotate90(mat);
return 0;
}
