Java Program to Sort the matrix row-wise and column-wise

Given a n x n matrix. The problem is to sort the matrix row-wise and column wise.
Examples:

Input : mat[][] = { {4, 1, 3},
                    {9, 6, 8},
                    {5, 2, 7} }
Output : 1 3 4
         2 5 7
         6 8 9

Input : mat[][] = { {12, 7, 1, 8},
                    {20, 9, 11, 2},
                    {15, 4, 5, 13},
                    {3, 18, 10, 6} } 
Output : 1 5 8 12
         2 6 10 15
         3 7 11 18
         4 9 13 20

Approach: Following are the steps:

1. Sort each row of the matrix.
2. Get transpose of the matrix.
3. Again sort each row of the matrix.
4. Again get transpose of the matrix.

Algorithm for getting transpose of the matrix:

for (int i = 0; i 
Java





// Java implementation to sort the
// matrix row-wise and column-wise
import java.util.Arrays;

class GFG
{
    static final int MAX_SIZE=10;

    // function to sort each row of the matrix
    static void sortByRow(int mat[][], int n)
    {
        for (int i = 0; i < n; i++)

            // sorting row number 'i'
            Arrays.sort(mat[i]);
    }

    // function to find transpose of the matrix
    static void transpose(int mat[][], int n)
    {
        for (int i = 0; i < n; i++)
            for (int j = i + 1; j < n; j++)
                {
                // swapping element at index (i, j)
                // by element at index (j, i)
                int temp=mat[i][j];
                mat[i][j]=mat[j][i];
                mat[j][i]=temp;
                }
    }

    // function to sort the matrix row-wise
    // and column-wise
    static void sortMatRowAndColWise(int mat[][],int n)
    {
        // sort rows of mat[][]
        sortByRow(mat, n);

        // get transpose of mat[][]
        transpose(mat, n);

        // again sort rows of mat[][]
        sortByRow(mat, n);

        // again get transpose of mat[][]
        transpose(mat, n);
    }

    // function to print the matrix
    static void printMat(int mat[][], int n)
    {
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < n; j++)
                System.out.print(mat[i][j] + " ");
            System.out.println();
        }
    }

    // Driver code
    public static void main (String[] args)
    {
        int mat[][] = { { 4, 1, 3 },
                        { 9, 6, 8 },
                        { 5, 2, 7 } };
        int n = 3;

        System.out.print("Original Matrix:
");
        printMat(mat, n);

        sortMatRowAndColWise(mat, n);

        System.out.print("
Matrix After Sorting:
");
        printMat(mat, n);
    }
}

// This code is contributed by Anant Agarwal.





Output: 
 
Original Matrix:
4 1 3
9 6 8
5 2 7

Matrix After Sorting:
1 3 4
2 5 7
6 8 9
Time Complexity: O(n2log2n). 
Auxiliary Space: O(1).

Please refer complete article on Sort the matrix row-wise and column-wise for more details!