let a = [
[1, 2, 3],
[4, 5, 6],
[7, 8, 9],
];
let b = [
[1, 2, 3],
[4, 5, 6],
[7, 8, 9],
];
let result = 0;
if (a.length === 3 && b.length === 3) {
console.log(a[0][0] + b[0][0], a[0][1] + b[0][1], a[0][2] + b[0][2]);
console.log(a[1][0] + b[1][0], a[1][1] + b[1][1], a[1][2] + b[1][2]);
console.log(a[2][0] + b[2][0], a[2][1] + b[2][1], a[2][2] + b[2][2]);
// this nested for loop shows the output in one line rather than in matrix form
/*
for (let row = 0; row <= 2; row++) {
for (let col = 0; col <= 2; col++) {
result = a[row][col] + b[row][col];
console.log(result);
}
}
*/
} else {
console.log("It works only for 3x3 matrix");
}