Given an n x n matrix in the given matrix, you have to print the elements of the matrix in the snake pattern.
Examples:
Input :mat[][] = { {10, 20, 30, 40},
{15, 25, 35, 45},
{27, 29, 37, 48},
{32, 33, 39, 50}};
Output : 10 20 30 40 45 35 25 15 27 29
37 48 50 39 33 32
Input :mat[][] = { {1, 2, 3},
{4, 5, 6},
{7, 8, 9}};
Output : 1 2 3 6 5 4 7 8 9
We traverse all rows. For every row, we check if it is even or odd. If even, we print from left to right else print from right to left.
PHP
<?php// PHP program to print // matrix in snake order$M= 4;$N =4;function printLN($mat){ global $M; global $N; // Traverse through all rows for ($i = 0; $i < $M; $i++) { // If current row is even, // print from left to right if ($i % 2 == 0) { for ($j = 0; $j < $N; $j++) echo $mat[$i][$j], " "; // If current row is odd, // print from right to left } else { for ($j = $N - 1; $j >= 0; $j--) echo $mat[$i][$j] , " "; } }}// Driver code$mat = array(array(10, 20, 30, 40), array(15, 25, 35, 45), array(27, 29, 37, 48), array(32, 33, 39, 50));printLN($mat);// This code is contributed by ajit ?> |
Output :
10 20 30 40 45 35 25 15 27 29 37 48 50 39 33 32
Time complexity: O(n^2) for given n*n matrix
Auxiliary space: O(1)
Please refer complete article on Print matrix in snake pattern for more details!
