message: Update Number of Students Doing Homework at a Given Time.cpp
diff: +// Difficulty : Easy
  +// https://leetcode.com/problems/number-of-students-doing-homework-at-a-given-time/
  +
  +
  class Solution {
  public:
  int busyStudent(vector<int>& startTime, vector<int>& endTime, int queryTime) {
  