PHP Program to Sort the matrix row-wise and column-wise
Last Updated :
22 Jul, 2024
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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:
Follow the below steps:
- Sort each row of the matrix.
- Get transpose of the matrix.
- Again sort each row of the matrix.
- Again get transpose of the matrix.
Algorithm for getting transpose of the matrix:
for (int i = 0; i < n; i++) {
for (int j = i + 1; i < n; i++) {
int temp = mat[i][j];
mat[i][j] = mat[j][i];
mat[j][i] = temp;
}
}
Below is the implementation of above approach:
<?php
// PHP implementation to sort
// the matrix row-wise and
// column-wise
$MAX_SIZE = 10;
// function to sort each
// row of the matrix
function sortByRow(&$mat, $n)
{
for ($i = 0; $i < $n; $i++)
// sorting row number 'i'
sort($mat[$i]);
}
// function to find
// transpose of the matrix
function transpose(&$mat, $n)
{
for ($i = 0; $i < $n; $i++)
{
for ($j = $i + 1;
$j < $n; $j++)
{
// swapping element at index (i, j)
// by element at index (j, i)
$t = $mat[$i][$j];
$mat[$i][$j] = $mat[$j][$i];
$mat[$j][$i] = $t;
}
}
}
// function to sort
// the matrix row-wise
// and column-wise
function sortMatRowAndColWise(&$mat, $n)
{
// sort rows of mat[][]
sortByRow($mat, $n);
// get transpose of mat[][]
transpose($mat, $n);
// again sort rows of mat[][]
sortByRow($mat, $n);
// again get transpose of mat[][]
transpose($mat, $n);
}
// function to print the matrix
function printMat(&$mat, $n)
{
for ($i = 0; $i < $n; $i++)
{
for ($j = 0; $j < $n; $j++)
echo $mat[$i][$j] . " ";
echo "
";
}
}
// Driver Code
$mat = array(array( 4, 1, 3 ),
array( 9, 6, 8 ),
array( 5, 2, 7 ));
$n = 3;
echo "Original Matrix:
";
printMat($mat, $n);
sortMatRowAndColWise($mat, $n);
echo "
Matrix After Sorting:
";
printMat($mat, $n);
// This code is contributed
// by ChitraNayal
?>
<?php// PHP implementation to sort // the matrix row-wise and // column-wise$MAX_SIZE = 10;// function to sort each// row of the matrixfunction sortByRow(&$mat, $n){ for ($i = 0; $i < $n; $i++) // sorting row number 'i' sort($mat[$i]);}// function to find// transpose of the matrixfunction transpose(&$mat, $n){ for ($i = 0; $i < $n; $i++) { for ($j = $i + 1; $j < $n; $j++) { // swapping element at index (i, j) // by element at index (j, i) $t = $mat[$i][$j]; $mat[$i][$j] = $mat[$j][$i]; $mat[$j][$i] = $t; } }}// function to sort // the matrix row-wise// and column-wisefunction sortMatRowAndColWise(&$mat, $n){ // sort rows of mat[][] sortByRow($mat, $n); // get transpose of mat[][] transpose($mat, $n); // again sort rows of mat[][] sortByRow($mat, $n); // again get transpose of mat[][] transpose($mat, $n);}// function to print the matrixfunction printMat(&$mat, $n){ for ($i = 0; $i < $n; $i++) { for ($j = 0; $j < $n; $j++) echo $mat[$i][$j] . " "; echo ""; }}// Driver Code$mat = array(array( 4, 1, 3 ), array( 9, 6, 8 ), array( 5, 2, 7 ));$n = 3;echo "Original Matrix:";printMat($mat, $n);sortMatRowAndColWise($mat, $n);echo "Matrix After Sorting:";printMat($mat, $n);// This code is contributed // by ChitraNayal?>Output
Original Matrix: 4 1 3 9 6 8 5 2 7 Matrix After Sorting: 1 3 4 2 5 7 6 8 9
Complexity Analysis:
- Time Complexity: O(n2log2n).
- Auxiliary Space: O(1).
Please refer complete article on Sort the matrix row-wise and column-wise for more details!
