Javascript Program to Print matrix in snake pattern

Given 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. 

Javascript

<script>

// Javascript program to print
// matrix in snake order
let M = 4;
let N = 4;

function print(mat)
{

    // Traverse through all rows
    for(let i = 0; i < M; i++)
    {

        // If current row is even, print from
        // left to right
        if (i % 2 == 0)
        {
            for(let j = 0; j < N; j++)
                document.write(mat[i][j] + " ");

        // If current row is odd, print from
        // right to left
        }
        else
        {
            for(let j = N - 1; j >= 0; j--)
                document.write(mat[i][j] + " ");
        }
    }
}

// Driver code
let mat = [ [ 10, 20, 30, 40 ],
            [ 15, 25, 35, 45 ],
            [ 27, 29, 37, 48 ],
            [ 32, 33, 39, 50 ] ];

print(mat);

// This code is contributed by rameshtravel07
</script>

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!