数据结构与算法

基础排序: 适用于数据量比较小的场景

1.冒泡排序

int arr[] = {6,4,3,5,1,2};
 for (int i = 0 ; i < arr.length ; i++){
     for (int j= 0 ; j < arr.length - 1 ; j++){
         if(arr[i] > arr[j]){
             int k = arr[i];
             arr[i] = arr[j];
             arr[j] = k;
         }
     }
 }
 for (int i = arr.length - 1 ; i > 0 ; i--){
     for (int j = 0 ; j < i ; j++){
 
         if(arr[i] > arr[j]){
             int k = arr[i];
             arr[i] = arr[j];
             arr[j] = k;
         }
     }
 }

2.选择排序

int arr[] = {6,4,3,5,1,2};
 
 for (int i = 0 ; i < arr.length - 1 ; i ++){
     int mix = i;
     for (int j = i+1 ; j < arr.length ; j++){
         if(arr[mix] > arr[j]){
             mix = j;
         }
     }
     int temp = arr[i];
     arr[i] = arr[mix];
     arr[mix] = temp;
 
 }
 System.out.println(Arrays.toString(arr));

3.插入排序

int arr[] = {6,4,3,5,1,2};
 
  for (int i = 1 ; i < arr.length  ; i++){
      for (int j = i; j >0 ; j--){
          if(arr[j] < arr[j-1]){
              int temp = arr[j];
              arr[j] = arr[j-1];
              arr[j-1] = temp;
          }else{
              break;
          }
      }
  }
  System.out.println(Arrays.toString(arr));