SpiralMatrix

const number = 4;

const matrix = Array.from({ length: number}); // number [empty]

for(let i = 0; i < number; i++){
    matrix[i] = [];
}
let n = 4;
let counter = 1;
let startRow = 0;
let endRow = n - 1;
let startCol = 0;
let endCol = n - 1;

while(startCol <= endCol && startRow <= endRow) {
    for(let i = startCol; i <= endRow; i++){
        matrix[i][startCol] = counter;
        counter++;
    }
    startCol++;

    for(let i = startCol; i <= endCol; i++){
        matrix[endCol][i] = counter;
        counter++;
    }

    endRow--;

    for(let i = endRow; i >= startRow; i--){
        matrix[i][endCol] = counter;
        counter++;
    }

    endCol--;

    for(let i = endCol; i >= startCol; i--){
        matrix[startRow][i] = counter;
        counter++;
    }
    startRow++;
}

console.table(matrix);