java 数组

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*数组的排序.使用方法: Arrays.sort();
* 可以使用冒泡排序
*
* **/
public class Arraysort {
public static void main(String[] args) {
int[] arr={2,4,5,6,1,77,45,88,34,354,234};
OutArray(arr);//打印数组
// ArraySort(arr);//排序数组
maopao(arr);
OutArray(arr);//打印数组
int a=Arrays.binarySearch(arr, 5);
int b=BinarySearch(arr, 5);
System.out.println(a);
System.out.println(b);
}

public static void maopao(int [] 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]){                int temp =arr[j];                arr[j]=arr[j+1];                arr[j+1]=temp;            }        }    }}public static int[]  ArraySort(int[] arr){//冒泡排序    for (int i = 0; i < arr.length; i++) {        for (int j = i+1; j < arr.length-1-i; j++) {            if(arr[i]>arr[j]){                int num=arr[i];                arr[i]=arr[j];                arr[j]=num;            }        }    }    return arr;}//定义方法,打印数组public static void OutArray(int[] arr){    System.out.print("[ ");    for (int i = 0; i < arr.length; i++) {        System.out.print(arr[i]+" ");    }    System.out.println("]");}//数组的查找     二分查找//binarysearch();//      int[] arr={2,4,5,6,1,77,45,88,34,354,234};public static int BinarySearch(int[] arr,int key){        int max=arr.length-1;        int min=0;        int mid = (max+min)/2;        for (int i = 0; i < arr.length; i++) {              if(key!=arr[mid]){                  if(key>arr[mid]){                      min=mid+1;                  }else                  if(key<arr[mid]){                      max=mid-1;                  }else{                      return -1;                  }                  mid=(max+min)/2;              }        }        return mid;}

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