题解 | #二分查找#

import java.util.*;

public class BinarySearch {
    public int getPos(int[] A, int n, int val) {
        // write code here
        int low=0,higth=n,res=-1;
        while (low != higth){
            int mid = (low + higth)/2;
            if (A[mid] > val){
                higth = mid;
            }else if (A[mid] < val){
                low = mid;
                if (res != -1){
                    break;
                }
            }else {
                res = mid;
                higth = mid;
            }
        }
        return res;
    }
}