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Number of Students Doing Homework at a Given Time

Given two integer arrays startTime and endTime and given an integer queryTime .
The ith student started doing their homework at the time startTime[ i ] and finished it at the time endTime[ i ] .

Return the number of students doing their homework at time queryTime . 

Example 1: 

Input: startTime = [1,2,3], endTime = [3,2,7], queryTime = 4
Output: 1
Explanation: We have 3 students where:
The first student started doing homework at time 1 and finished at time 3 and wasn't doing anything at time 4.
The second student started doing homework at time 2 and finished at time 2 and also wasn't doing anything at time 4.
The third student started doing homework at time 3 and finished at time 7 and was the only student doing homework at time 4.

Example 2: 

Input: startTime = [4], endTime = [4], queryTime = 4
Output: 1
Explanation: The only student was doing their homework at the queryTime.

Example 3: 

Input: startTime = [4], endTime = [4], queryTime = 5
Output: 0

Example 4: 

Input: startTime = [1,1,1,1], endTime = [1,3,2,4], queryTime = 7
Output: 0

Example 5: 

Input: startTime = [9,8,7,6,5,4,3,2,1], endTime = [10,10,10,10,10,10,10,10,10], queryTime = 5
Output: 5

Constraints:

  • startTime.length == endTime.length
  • 1 <= startTime.length <= 100
  • 1 <= startTime[i] <= endTime[i] <= 1000
  • 1 <= queryTime <= 1000


Java


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public class MyClass {
    public static void main(String args[]) {
      int[] startTime = { 1,2,3 };
      int[] endTime = { 3,2,7 };
      int queryTime = 4;
      System.out.println(findStudents(startTime, endTime, queryTime));
    }
    public static int findStudents(int[] startTime, int[] endTime, int queryTime){
        int noOfStudents = 0;
        for(int i=0; i<startTime.length; i++){
            if(startTime[i] <= queryTime && endTime[i] >= queryTime)
                noOfStudents += 1;
        }
        return noOfStudents;
    }
 }

Python


def findStudents(startTime, endTime, queryTime):
        noOfStudents = 0;
        for i in range(0,len(startTime)):
            if startTime[i] <= queryTime <= endTime[i]:
                noOfStudents += 1
        return noOfStudents

startTime = [ 1, 2, 3 ]
endTime = [ 3,2,7 ]
queryTime = 4
print(findStudents(startTime, endTime, queryTime))