题解 | #二分查找-II#

import java.util.*;


public class Solution {
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     * 如果目标值存在返回下标，否则返回 -1
     * @param nums int整型一维数组 
     * @param target int整型 
     * @return int整型
     */
    public int search (int[] nums, int target) {
        // write code here
        int low = 0;
        int high = nums.length-1;
        while(low<=high){
            int mid = (low+high) / 2;
            if(nums[mid] == target){
                while(mid > 0 && nums[mid-1] == nums[mid]) mid--;
                return mid;
            } else if(nums[mid]>target){
                high = mid - 1;
            } else {
                low = mid + 1;
            }
        }
        return -1;
    }
}