This question I've heard from friend of mine who, recently, had a phone interview with AirBnB.

Here is the question:

Total booking price = base price + service fee + cleaning fee + ...

Create a function which satisfy following condition:
Input: An array of decimals ~ X
Output: An array of integers ~ Y

sum(Y) = round(sum(x))
minimize the value of (|y1-x1| + |y2-x2| +… + |yn-xn|)

Example 1:
input = [0.3, 0.5, 0.6, 0.8, 0.9, 2.1, 3.4]
output = [ 0, 1, 1, 1, 1, 2, 3 ]

Example 2:
input = [0.5, 7.6, 47.4]
output = [ 1, 8, 47 ]

I've decided to solve it in my free time using Javascript, here is my solution:

//let numbers = [0.3, 0.5, 0.6, 0.8, 0.9, 2.1, 3.4]; // input
//let numbers = [0.7, 0.7, 0.8];
//let numbers = [0.1, 0.1, 0.1, 0.1, 0.1, 0.1, 0.1, 0.1, 0.1, 0.1, 0.1];
//let numbers = [3.7, 1.7, 0.8];
let numbers = [0.5, 7.6, 47.4];

function roundNumbers(input) {
  let flooredNumbers = input.map(function(a){return Math.floor(a)});
  let sumLeft = Math.round(sum(input)) - sum(flooredNumbers);
  let sorted = [];
  input.forEach(function(a,i){
    sorted.push({
      idx: i,
      elm: (a-Math.floor(a))
    })
  });
  sorted.sort(function(a,b){ return b.elm - a.elm});
  let i = 0;
  while(i < sumLeft) {
    flooredNumbers[sorted[i].idx] += 1;
    i++;
  }
  return flooredNumbers;
}

function sum(arr) {
  return arr.reduce((a, b) => a + b, 0);
}

roundNumbers(numbers);