function Arrays_sum(array1, array2) { var result = []; var ctr = 0; var x=0; if (array1.length === 0) return "array1 is empty"; if (array2.length === 0) return "array2 is empty"; while (ctr < array1.length && ctr < array2.length) { result.push(array1[ctr] + array2[ctr]); ctr++; } if (ctr === array1.length) { for (x = ctr; x < array2.length; x++) { result.push(array2[x]); } } else { for (x = ctr; x < array1.length; x++) { result.push(array1[x]); } } return result; } console.log(Arrays_sum([1,0,2,3,4], [3,5,6,7,8,13]));