Java big data platform development study notes (9)-insertion sort

1. Data structure and algorithm:

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1.1. Create an insertion sort method:

 public static void insertSortDemo(int[] arr){
    
    
     for(int i=1; i<arr.length; i++){
    
    
         int value = arr[i];
         int index = i;
         while(index > 0){
    
    
             if(arr[index-1] > value){
    
    
                 arr[index] = arr[index-1];
             }else{
    
    
                 break;
             }
             index--;
         }
         arr[index] = value;
     }
 }
 

1.2. Main method:

public static void main(String[] args) {
    
    
    //随机创建8万 个数据
    int arr[]= new int[80000];
    for(int i=0; i<arr.length; i++){
    
    
        arr[i] = (int)(Math.random()*80000);
    }
    //计算 冒泡排序时间
    double start = System.currentTimeMillis();
    System.out.println("计时开始：");
    insertSortDemo(arr);//此处写要测试的代码
    double end = System.currentTimeMillis();
    System.out.println("计时结束, 共耗时:"+ (double)((end-start)/1000) +"秒");
}
    

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• Written by ChiKong_Tam on September 9, 2020