Day 22B of Scrimba JavaScriptmas — Extract Matrix Column

This is the second challenge that pop up today in #scrimba #javascriptmas challenge. It totally different with 22A for me. It a lot easier. Or perhaps, i understand how to solve this because i finish the code before, i don’t know. The fact is i just need about 10–15 minutes to solve this. And the before i need almost 2–3 hours.

So this challenge is asking us, to give the value of column inside three array.

const matrix = [[1, 1, 1, 2], [0, 5, 0, 4], [2, 1, 3, 6]];
const column = 2;
// Result = [1, 0, 3]

After thinking about the algorithm it can be solved by using nested for loop statement. So the first thing i do, i build an empty array to contain the answer. Next, i build nested for loop, the first is two iterate the matrix, and the second is to iterate the index of the matrix. And after second iteration using push function, i save the value of matrix[i][2] into an empty array that i declare before. Don’t forget to use break, to stop, if iteration complete. Here is my solution code.

function extractMatrixColumn(matrix, column) {
    //  write code here.
    const matrixColumn = []
    
    for(i = 0; i<matrix.length;i++){
        for(j=0;j<matrix[i].length;j++){
            matrixColumn.push(matrix[i][2]);
            break;
        }
    }
    
    return matrixColumn
}

And here is the link for my answer

Note at 1:33

Hope u can do it better than me, Thanks!!!