java二分查找

Posted 2021-11-11 oldfour

java二分查找

import java.util.Arrays;

public class TestBianarySearch3 {
    public static void main(String[] args) {
        int [] arr = {23,34,45,65,26,76,86,45,765,43};
        Arrays.sort(arr);
        System.out.println(Arrays.toString(arr));
        System.out.println(BianarySearchResult(arr,45)+1);
        
    }
    public static int BianarySearchResult(int[] arr,int result) {
        int low = 0;
        int high = arr.length-1;
        while(low<=high) {
            int mid = (low+high)/2;
            if( arr[mid] == result) {
                return mid;
            }
            if(result<arr[mid]) {
                high = mid-1;
            }
            if(result>arr[mid]) {
                low = high+1;
            }                
        }
        return -1;
    }
    
}