[算法解腻]-排序

一、冒泡排序

function swap(array, index1, index2) {
  [array[index1], array[index2]] = [array[index2], array[index1]];
}

function sort(array) {
  const len = array.length;
  for (let i = 0; i < len; i++) {
     let min = j;
     for (let j = i + 1; j < len; j++) {
        if (array[j] < array[i]) {
          min = j;
        }
        swap(array, i, min);
     }
  }
  
  return array;
}

二、插入排序

function sort(array) {
  const len = array.length;
  for (let i = 0; i < len; i++) {
    for (let j = i; j > 0 && array[j] < array[j-1]; j--) {
      swap(array, j, j - 1);
    }
  }
  
  return array;
}

三、快速排序

function swap(nums, index1, index2) {
  [nums[index1], nums[index2]] = [nums[index2], nums[index1]];
}
function paration(nums, start, end) {
  const random = Math.floor(Math.random() * (end - start + 1)) + start;
  swap(nums, random, end);
  let small = start - 1;
  for (let i = start; i <= end; i++) {
      if (nums[i] < nums[end]) {
         small++;
         swap(nums, i, small);
      }
  }
  small++;
  swap(nums, small, end);
  return small;
}

function quickSort(nums, start, end) {
   if(start < end) {
     const privot = paration(nums, start, end);
     quickSort(nums, start, privot - 1);
     quickSort(nums, privot + 1, end);
   }
   
   return nums;
}
function sort(nums) {
   return quickSort(nums, 0, nums.length - 1);
}