Leetcode-2080区间内查询数字的频率

最近没有更新不是没做，单纯是有些懒，不知道说点啥了

链接如下，2080. 区间内查询数字的频率

感觉我的做法有些暴力，用一个hashmap存的字符串对应的值，发现完全没用到二分查找的思想，能过也是奇迹了。

C++代码如下

class RangeFreqQuery {
public:vector<int> R_arr;unordered_map<string,int> hmap;RangeFreqQuery(vector<int>& arr) {R_arr = arr;}int query(int left, int right, int value) {int cnt = 0;if(hmap.find(to_string(left)+'.'+to_string(right)+'.'+to_string(value))!= hmap.end()){cnt = hmap[to_string(left)+'.'+to_string(right)+'.'+to_string(value)] ;return cnt;}for(int i = left;i<=right;i++){if(R_arr[i] == value)cnt++;}hmap[to_string(left)+'.'+to_string(right)+'.'+to_string(value)] = cnt;return cnt;}
};/*** Your RangeFreqQuery object will be instantiated and called as such:* RangeFreqQuery* obj = new RangeFreqQuery(arr);* int param_1 = obj->query(left,right,value);*/