Algorithmes

algorithmes.js

/*
 * Commons array
 * when array is sorted
 */
function commons(a, b) {
  const result = [];
  let i = j = 0;  
  cancel:while (true) {
    if (a[i] > b[j]) j++;
    else if (a[i] < b[j]) i++;
    else {
      result.push(a[i]);
      i++;
      j++;
    }  
    
    if(i === a.length || j === b.length) break cancel;
  }
  return result;
}

/*
 * Multiple
 * with sum recursive
 */
function multiple(a, b) {
  if (b === 0) return 0;
  return multiple(a, b - 1) + a;
}

/*
 * Factorielle
 * https://fr.wikipedia.org/wiki/Factorielle
 */
function factorielle(n) {
  if (n === 0) return 1;
  return n * factorielle(n - 1);
}

/*
 * Binary Search
 * https://fa.wikipedia.org/wiki/%D8%A7%D9%84%DA%AF%D9%88%D8%B1%DB%8C%D8%AA%D9%85_%D8%AC%D8%B3%D8%AA%D8%AC%D9%88%DB%8C_%D8%AF%D9%88%D8%AF%D9%88%DB%8C%DB%8C
 */
function binarySearch(arr, x, start, end) {
  if (start > end) return -1;
  let mid = Math.floor((start + end) / 2);
  if (arr[mid] === x) return mid;
  if (arr[mid] > x) return binarySearch(arr, x, start, mid - 1);
  else return binarySearch(arr, x, mid + 1, end);
}

/*
 * Binary Search
 * find exist item
 */
function binarySearch(array, search) {
  const mid = Math.floor(array.length / 2);
  if (array[mid] === search) return true;
  if (array[mid] < search) return binarySearch(array.slice(mid + 1), search);
  if (array[mid] > search) return binarySearch(array.slice(0, mid), search);
  return false;
}

/*
 * Bubble Sort
 */
function bubbleSort(array) {
  const length = array.length;

  for (let i = 0; i < length-1; i++){
    for (let j = 0; j < length-1; j++){
      if (array[j] > array[j + 1]) {
        const temp = array[j + 1];
        array[j + 1] = array[j];
        array[j] = temp;
      }
    }
  }
  
  return array;
}

/**
 * Selection Sort
 */
function selectionSort(array) {
  const lenght = array.length;
  for (let i = 0; i < lenght; i++) {
    let minValueIndex = i;

    for (let j = n + 1; j < lenght; j++) {
      if (array[j] < array[minValueIndex]) {
        minValueIndex = j;
      }
    }

    const temp = array[i];
    array[i] = array[minValueIndex];
    array[minValueIndex] = temp;
  }
  return array;
}