Google - Array plus 1

by Anton Bagayev

HTML

<p id="output"></p>

JavaScript

function plus_one(array){ //[9, 9]
	let result = array;
  let carryOver = 1;
  
  for (let i = array.length-1; i >= 0; i--) {
  	let curr_sum = array[i] + carryOver;
    //alert(curr_sum);
    if (curr_sum < 10) {
    	array[i] = curr_sum;
      carryOver = 0;
    } else {
    	carryOver = Math.floor(curr_sum / 10);
      array[i] = curr_sum - (carryOver*10);
    }
  }
  if (carryOver > 0) {
  	result.unshift(carryOver);
  }
  
	return result;
}


let new_arr = plus_one([8,9,9,9]);
document.getElementById("output").innerHTML = new_arr;