牛客-剑指0ffer-数字在排序数组中出现的次数

题目描述
统计一个数字在排序数组中出现的次数。

class Solution {
public:
    int GetNumberOfK(vector<int> data ,int k) {
        return biSearch(data,k+0.5) - biSearch(data,k-0.5);
    }
    int biSearch(vector<int> data,double num){
        int s = 0,e = data.size()-1;
        while (s <=e){
            int mid = s+(e-s) / 2;
            if (data[mid] < num){
                s = mid+1;
            }
            else if(data[mid] > num){
                e = mid -1;
            }
        }
        return s;
    }
};