const bubbleSort = array => {
  const arr = Array.from(array); // avoid side effects
  for (let i = 1; i < arr.length; i++) {
    for (let j = 0; j < arr.length - i; j++) {
      if (arr[j] > arr[j + 1]) {
        [arr[j], arr[j + 1]] = [arr[j + 1], arr[j]];
      }
    }
  }
  console.log(arr);
};
const input = readline();
const words = input.split(" ");
const letter = [];
for (i = 0; i < input.length; i++){
	letter.push(input[i])
}
 
bubbleSort(letter);

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