题解 | #数字在升序数组中出现的次数#

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
     *
     *
     * @param nums int整型一维数组
     * @param k int整型
     * @return int整型
     */
      static int index=-1;记录目标字符是否出现
    public int GetNumberOfK (int[] nums, int k) {
        // write code here
        int res = 0;
        getNumber(nums, 0, nums.length - 1, k);
        if(index==-1){
            return 0;
        }else{
            res++;
            int l=index-1;int r=index+1;
            while(l>=0&&nums[l]==k){
                res++;
                l--;
            }
            while(r<nums.length&&nums[r]==k){
                res++;
                r++;
            }
        }
        return res;
    }
    public void getNumber(int[] nums, int left, int right, int k) {
        if (left > right) {
            return;
        }
        int midIndex = left + (right - left) / 2;
        if (nums[midIndex] == k) {
             index=midIndex;
        } else if (nums[midIndex] > k) {
            right = midIndex - 1;
            getNumber(nums, left, right, k);
        } else {
            left = midIndex + 1;
            getNumber(nums, left, right, k);
        }
    }
}