Program to calculate Percentile of a student based on rank

Given the rank of a student and the total number of students appearing in an examination, the task is to find the percentile of the student. 

The percentile of a student is the % of the number of students having marks less than him/her.

Examples:

Input: Rank: 805, Total Number of Students Appeared: 97481 
Output: 99.17 
Explanation: 
((97481 – 805) / 97481) * 100 = 99.17
Input: Rank: 65, Total Number of Students Appeared: 100 
Output: 35 
Explanation: 
((100 – 65) / 100) * 100 = 35 

Approach
The formula to calculate the percentile when the rank of the student and the total number of students appeared is given is:

((Total Students – Rank) / Total Students) * 100

Below is the implementation of the above formula: 

C++ 

C++

// C++ program to calculate Percentile
// of a student based on rank

#include <bits/stdc++.h>
using namespace std;

// Program to calculate the percentile
float getPercentile(int rank, int students)
{
    // flat variable to store the result
    float result = float(students - rank)
                / students * 100;

    // calculate and return the percentile
    return result;
}

// Driver Code
int main()
{
    int your_rank = 805;
    int total_students = 97481;

    cout << getPercentile(
        your_rank, total_students);
}

Java

// Java program to calculate Percentile
// of a student based on rank
import java.util.*;

class GFG{

// Program to calculate the percentile
static float getPercentile(int rank, int students)
{
    // flat variable to store the result
    float result = (float)(students - rank)
                   / students * 100;

    // calculate and return the percentile
    return result;
}

// Driver Code
public static void main(String[] args)
{
    int your_rank = 805;
    int total_students = 97481;

    System.out.print(getPercentile(
        your_rank, total_students));
}
}

// This code is contributed by Princi Singh

Python3

# Python3 program to calculate Percentile
# of a student based on rank

# Program to calculate the percentile
def getPercentile(rank, students) :

    # flat variable to store the result
    result = (students - rank) / students * 100;

    # calculate and return the percentile
    return result;

# Driver Code
if __name__ == "__main__" :

    your_rank = 805;
    total_students = 97481;

    print(getPercentile(your_rank, total_students));

# This code is contributed by Yash_R

C#

// C# program to calculate Percentile
// of a student based on rank
using System;

class GFG{

// Program to calculate the percentile
static float getPercentile(int rank, int students)
{
    // flat variable to store the result
    float result = (float)(students - rank)
                   / students * 100;

    // calculate and return the percentile
    return result;
}

// Driver Code
public static void Main(String[] args)
{
    int your_rank = 805;
    int total_students = 97481;

    Console.Write(getPercentile(
        your_rank, total_students));
}
}

// This code is contributed by Princi Singh

Javascript

<script>

// JavaScript program to calculate Percentile
// of a student based on rank

    // Program to calculate the percentile
    function getPercentile(rank , students)
    {
        // flat variable to store the result
        var result =  (students - rank) / students * 100;

        // calculate and return the percentile
        return result;
    }

    // Driver Code

        var your_rank = 805;
        var total_students = 97481;

        document.write(getPercentile(your_rank, total_students).toFixed(4));

// This code contributed by aashish1995

</script>

Output:

99.1742

Performance Analysis: 

• Time Complexity: In the above approach, we are able to calculate percentile using a formula in constant time, so the time complexity is O(1). 
  
• Auxiliary Space Complexity: In the above approach, we are not using any extra space apart from a few constant size variables, so Auxiliary space complexity is O(1).