Java——选择、冒泡排序、折半查找

 1     //选择排序对数据进行升序排序
 2         public static void selectSortArray(int[] arr){
 3             for(int i = 0; i<arr.length-1;i++){
 4                 for(int j = i+1;j<arr.length;j++){
 5                     if(arr[i]>arr[j]){
 6                         int temp = arr[j];
 7                         arr[j] = arr[i];
 8                         arr[i] = temp;
 9                      }
10                 }
11             }
12         }
13    

    //冒泡排序对数据进行升序排序
    public static void bubbleSortArray(double[] arr){
        for(int i = 0;i<arr.length-1;i++){
            for(int j = 0;j<arr.length-1-i;j++){
                if(arr[j]>arr[j+1]){
                    double temp = arr[j+1];
                    arr[j+1] = arr[j];
                    arr[j] = temp;
                    }
            }
        }
    }

    public static int binarySearch(int[] arr,int key){
        int max,min,mid;
        max = arr.length-1;
        min = 0;
        while(min<=max){
            mid = (max+min)/2;
            if(key>arr[mid]){
                min = mid+1;
            }else if (key<arr[mid]) {
                max = mid-1;
            }else{
                return mid;
            }
        }
        return -1;
    }