剑指offer 数字在排序数组中出现的次数

class Solution {
public:
    int GetNumberOfK(vector<int> data ,int k) {
        int length=data.size();
        if(length==0) return 0;
        return getnumberofk(data,0,length-1,k);
    }
    int getnumberofk(vector<int>data,int start,int end,int k){
        int count=0;
        int middle=start+(end-start)/2;
        if(data[start]>k||data[end]return 0;
        if(data[start]==k){
            for(int i=start;i<=end&&data[i]==k;i++){
                count++;
            }
            return count;
        }
        if(data[end]==k){
            for(int i=end;i>=start&&data[i]==k;i--)
                count++;
            return count;
        }
        return getnumberofk(data,start,middle,k)+getnumberofk(data,middle+1,end,k);
    }
};