CodeSignal - Arcade - Intro - JS - matrixElementsSum

matrixElementsSum.js

function matrixElementsSum(matrix) {
    let sum = 0 ;
    for(let j = 0; j < matrix[0].length; j++) {
        let i = 0;
        while(i < matrix.length && matrix[i][j] != 0 ){
            sum += matrix[i][j];
            i++;
        }
    }
    return sum;
}