Program to find the Discount Percentage

Given Marked Price and Selling price as of a product. The task is to calculate the Discount Percentage applied to that product.

Examples:  

Input: M = 120, S = 100
Output: 16.66%

Input: M = 1000, S = 500
Output: 50% 

The mathematical formula to calculate the Discount Percentage for the product is: 

Discount = Marked Price - Selling price

Therefore,
Discount Percentage = (Discount / Marked Price) * 100

Below is the program to find the discount percentage for a product:  

C++

// CPP Program to find the Discount Percentage

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

// Function to find the Discount Percentage
float discountPercentage(float S, float M)
{
    // Calculating discount
    float discount = M - S;

    // Calculating discount percentage
    float disPercent = (discount / M) * 100;

    return disPercent;
}

// Driver code
int main()
{
    int M, S;
    M = 120;
    S = 100;

    // Setting the precision to 2 decimals
    cout << std::fixed << std::setprecision(2)
        << discountPercentage(S, M) << "%" << endl;

    M = 1000;
    S = 500;

    // Setting the precision to 2 decimals
    cout << std::fixed << std::setprecision(2)
        << discountPercentage(S, M) << "%" << endl;

    return 0;
}

Java

// Java Program to find the Discount Percentage

import java.util.*;
import java.lang.*;
import java.io.*;

class GFG{

// Function to find the Discount Percentage
static float discountPercentage(float S, float M)
{
    // Calculating discount
    float discount = M - S;

    // Calculating discount percentage
    float disPercent = (discount / M) * 100;

    return disPercent;
}

// Driver code
public static void main(String args[])
{
    int M, S;
    M = 120;
    S = 100;

    System.out.printf("%.2f",discountPercentage(S,M));
    System.out.println("%");


    M = 1000;
    S = 500;

   System.out.printf("%.2f",discountPercentage(S,M));
    System.out.println("%");
}
}

Python3

# Python3 Program to find the
# Discount Percentage

# Function to find the
# Discount Percentage
def discountPercentage(S, M):

    # Calculating discount
    discount = M - S

    # Calculating discount percentage
    disPercent = (discount /M) * 100

    return disPercent


# Driver code
if __name__=='__main__':
    M = 120
    S = 100

    print(discountPercentage(S, M), "%")

    M = 1000
    S = 500

    print(discountPercentage(S, M), "%")

# This code is contributed
# by ihritik

C#

// C# Program to find the
// Discount Percentage
using System;

class GFG
{

// Function to find the
// Discount Percentage
static float discountPercentage(float S,
                                float M)
{
    // Calculating discount
    float discount = M - S;

    // Calculating discount percentage
    float disPercent = (discount / M) * 100;

    return disPercent;
}

// Driver code
static public void Main ()
{
    int M, S;
    M = 120;
    S = 100;

    Console.Write(discountPercentage(S, M));
    Console.WriteLine("%");

    M = 1000;
    S = 500;

    Console.Write(discountPercentage(S, M));
    Console.Write("%");
}
}

// This code is contributed by Raj

PHP

<?php
// PHP Program to find the
// Discount Percentage

// Function to find the
// Discount Percentage
function discountPercentage($S, $M)
{
    // Calculating discount
    $discount = $M - $S;

    // Calculating discount percentage
    $disPercent = ($discount /$M) * 100;

    return $disPercent;
}

// Driver code
$M; $S;
$M = 120;
$S = 100;

echo discountPercentage($S, $M), "%", "\n";

$M = 1000;
$S = 500;

echo discountPercentage($S, $M), "%", "\n";

// This code is contribute
// by inder_verma
?>

Javascript

<script>

// Java Script Program to find the Discount Percentage



// Function to find the Discount Percentage
function discountPercentage( S,  M)
{
    // Calculating discount
    let discount = M - S;

    // Calculating discount percentage
    let disPercent = (discount / M) * 100;

    return disPercent;
}

// Driver code
 let M, S;
    M = 120;
    S = 100;

    document.write(discountPercentage(S,M).toFixed(2));
    document.write("%");
    document.write("<br>");

    M = 1000;
    S = 500;

    document.write(discountPercentage(S,M).toFixed(2));
    document.write("%");

// Contributed by sravan kumar
</script>

Output:

16.67%
50.00%

Time Complexity: O(1), since there is no loop or recursion.
Auxiliary Space: O(1), since no extra space has been taken.

Approach#2: Using division formula

Algorithm

1. Divide the selling price (S) by the marked price (M) to get the fraction.
2. Subtract the fraction from 1 to get the discount fraction.
3. Multiply the discount fraction by 100 to get the discount percentage.
4. Return the discount percentage.

Python3

def discount_percentage(M, S):
    fraction = S / M
    discount_fraction = 1 - fraction
    percentage = discount_fraction * 100
    return f"{percentage:.2f}%"

M = 120
S = 100
print(discount_percentage(M, S))

Javascript

function discount_percentage(M, S) {
    let fraction = S / M;
    let discount_fraction = 1 - fraction;
    let percentage = discount_fraction * 100;
    return percentage.toFixed(2) + "%";
}

let M = 120;
let S = 100;
console.log(discount_percentage(M, S));

Output

16.67%

Time Complexity: O(1)
Space Complexity: O(1)