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. 

let M = 4;
let N = 4;

function print(mat) {
    let output = "";

    // 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++)
                output += mat[i][j] + " ";

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

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

print(mat);

10 20 30 40 45 35 25 15 27 29 37 48 50 39 33 32

Complexity Analysis:

• Time complexity: O(n^2) for given n*n matrix
• Auxiliary space: O(1)

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