Área de un cuadrado a partir de la longitud de la diagonal

Dado un número d que es la longitud de la diagonal de un cuadrado, encuentre su área. 
Ejemplos: 
 

Input : d = 10
Output : Area = 50

Input : d = 12.2
Output : Area = 74.42

El área de un cuadrado se puede calcular como (d * d)/2. Por favor vea la imagen de abajo para más detalles.
 

// C++ Program to find the area of square
// when its diagonal is given.
#include <bits/stdc++.h>
using namespace std;
 
// Returns area of square from given
// diagonal
double findArea(double d)
{
    return (d * d) / 2.0;
}
 
// Driver Code
int main()
{
    double d = 10;
    cout << (findArea(d));
    return 0;
}
 
// This code is contributed by
// Shivi_Aggarwal

// C Program to find the area of square
// when its diagonal is given.
#include <stdio.h>
 
// Returns area of square from given
// diagonal
double findArea(double d)
{
    return (d * d) / 2;
}
 
// Driver function.
int main()
{
    double d = 10;
    printf("%.2f", findArea(d));
    return 0;
}

// Java Program to find the area of square
// when its diagonal is given.
 
class GFG
{
    // Returns area of square from given
    // diagonal
    static double findArea(double d)
    {
        return (d * d) / 2;
    }
     
    // Driver code
    public static void main (String[] args)
    {
        double d = 10;
        System.out.println(findArea(d));
    }
}
 
// This code is contributed by Anant Agarwal.

# Python3 Program to find
# the area of square
# when its diagonal is given.
 
# Returns area of square from given
# diagonal
def findArea(d):
 
    return (d * d) / 2
 
# Driver function.
d = 10
print("%.2f" % findArea(d))
 
# This code is contributed by
# Smitha Dinesh Semwal

// C# Program to find the area of square
// when its diagonal is given.
using System;
 
class GFG
{
    // Returns area of square from given
    // diagonal
    static double findArea(double d)
    {
        return (d * d) / 2;
    }
     
    // Driver code
    public static void Main ()
    {
        double d = 10;
        Console.WriteLine(findArea(d));
    }
}
 
// This code is contributed by vt_m.

<?php
// PHP Program to find the area of
// square when its diagonal is given.
 
// Returns area of square
// from given diagonal
function findArea( $d)
{
    return ($d * $d) / 2;
}
 
    // Driver Code
    $d = 10;
    echo( findArea($d));
     
// This code is contributed by vt_m.
?>

<script>
 
// JavaScript Program to find the area of square
// when its diagonal is given.
 
 // Returns area of square from given
    // diagonal
    function findArea(d)
    {
        return (d * d) / 2;
    }
  
// Driver code
 
       let d = 10;
       document.write(findArea(d));
       
</script>

50.00

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