Sum of elements whose square root is present in the array

Given an array arr[], the task is to find the sum of all those elements from the given array whose square root is present in the same array.

Examples:

Input: arr[] = {1, 2, 3, 4, 6, 9, 10} 
Output: 13 
4 and 9 are the only numbers whose square roots 2 and 3 are present in the array

Input: arr[] = {4, 2, 36, 6, 10, 100} 
Output: 140 

Naive Approach: To find the sum of elements whose square root is present in the given array, check for the square root of every element by iterating from arr[0] to arr[n] which will do the job but in O(n*n) complexity.

Below is the implementation of the above approach: 

C++

// CPP program to find the sum of all the elements
// from the array whose square root is present
// in the same array

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

    // Function to return the required sum
int getSum(int arr[], int n)
    {

        int sum = 0;

        for (int i = 0; i < n; i++) {
            double sqrtCurrent = sqrt(arr[i]);

            for (int j = 0; j < n; j++) {
                double x = arr[j];

                // If sqrtCurrent is present in array
                if (x == sqrtCurrent) {
                    sum += (sqrtCurrent * sqrtCurrent);
                    break;
                }
            }
        }

        return sum;
    }

    // Driver code
    int main()
    {
        int arr[] = { 2, 4, 5, 6, 7, 8, 9, 3 };
        int n = sizeof(arr)/sizeof(arr[0]);
        cout<<(getSum(arr, n));
    }
// This code is contributed by
// Surendra_Gangwar

Java

// Java program to find the sum of all the elements
// from the array whose square root is present
// in the same array
public class GFG {
    // Function to return the required sum
    public static int getSum(int arr[], int n)
    {

        int sum = 0;

        for (int i = 0; i < n; i++) {
            double sqrtCurrent = Math.sqrt(arr[i]);

            for (int j = 0; j < n; j++) {
                double x = arr[j];

                // If sqrtCurrent is present in array
                if (x == sqrtCurrent) {
                    sum += (sqrtCurrent * sqrtCurrent);
                    break;
                }
            }
        }

        return sum;
    }

    // Driver code
    public static void main(String args[])
    {
        int arr[] = { 2, 4, 5, 6, 7, 8, 9, 3 };
        int n = arr.length;
        System.out.println(getSum(arr, n));
    }
}

Python3

# Python3 program to find the sum of
# all the elements from the array
# whose square root is present in
# the same array
import math

# Function to return the required sum
def getSum(arr, n):
    sum = 0
    for i in range(0, n):
        sqrtCurrent = math.sqrt(arr[i])
        for j in range(0, n):
            x = arr[j]

            # If sqrtCurrent is present in array
            if (x == sqrtCurrent):
                sum += (sqrtCurrent *
                        sqrtCurrent)
                break
    return int(sum)

# Driver code
if __name__ == '__main__':

    arr = [ 2, 4, 5, 6, 7, 8, 9, 3]
    n = len(arr)
    print(getSum(arr, n))

# This code is contributed
# by 29AjayKumar

C#

// C# program to find the sum of all the elements
// from the array whose square root is present
// in the same array
using System ;

public class GFG {

    // Function to return the required sum
    public static float getSum(int []arr, int n)
    {

        float sum = 0;

        for (int i = 0; i < n; i++) {
            float sqrtCurrent = (float)Math.Sqrt(arr[i]);

            for (int j = 0; j < n; j++) {
                float x = (float)arr[j];

                // If sqrtCurrent is present in array
                if (x == sqrtCurrent) {
                    sum += (sqrtCurrent * sqrtCurrent);
                    break;
                }
            }
        }

        return sum;
    }

    // Driver code
    public static void Main()
    {
        int []arr = { 2, 4, 5, 6, 7, 8, 9, 3 };
        int n = arr.Length;
        Console.WriteLine(getSum(arr, n));
    }
    // This code is contributed by Ryuga
}

PHP

<?php
// PHP program to find the sum of all
// the elements from the array whose
// square root is present in the same array

// Function to return the required sum
function getSum(&$arr, $n)
{
    $sum = 0;

    for ($i = 0; $i < $n; $i++)
    {
        $sqrtCurrent = sqrt($arr[$i]);

        for ($j = 0; $j < $n; $j++)
        {
            $x = $arr[$j];

            // If sqrtCurrent is present in array
            if ($x == $sqrtCurrent)
            {
                $sum += ($sqrtCurrent * $sqrtCurrent);
                break;
            }
        }
    }

    return $sum;
}

// Driver code
$arr = array(2, 4, 5, 6, 7, 8, 9, 3);
$n = sizeof($arr);
echo (getSum($arr, $n));

// This code is contributed
// by Shivi_Aggarwal
?>

Javascript

<script>
    // Javascript program to find the sum of all the elements
    // from the array whose square root is present
    // in the same array

    // Function to return the required sum
    function getSum(arr, n)
    {

        let sum = 0;

        for (let i = 0; i < n; i++) {
            let sqrtCurrent = Math.sqrt(arr[i]);

            for (let j = 0; j < n; j++) {
                let x = arr[j];

                // If sqrtCurrent is present in array
                if (x == sqrtCurrent) {
                    sum += (sqrtCurrent * sqrtCurrent);
                    break;
                }
            }
        }

        return sum;
    }

    let arr = [ 2, 4, 5, 6, 7, 8, 9, 3 ];
    let n = arr.length;
    document.write(getSum(arr, n));

    // This code is contributed by suresh07.
</script>

Output

13

Complexity Analysis:

• Time Complexity: O(n²)
• Auxiliary Space: O(1)

Efficient Approach: We can create a HashSet of all the elements present in the array and then check for the square root of each element of the array in O(n) time.

Below is the implementation of the above approach:  

C++

// C++ program to find the sum of all the elements
// from the array whose square root is present
// in the same array
#include<bits/stdc++.h>
using namespace std;

// Function to return the required sum
int getSum(int arr[], int n)
{

    int i, sum = 0;

    // Initialization of hash map
    set<int> hashSet;

    // Store each element in the hash map
    for (i = 0; i < n; i++)
        hashSet.insert(arr[i]);

    for (i = 0; i < n; i++)
    {
        double sqrtCurrent = sqrt(arr[i]);

        // If sqrtCurrent is a decimal number
        if (floor(sqrtCurrent) != ceil(sqrtCurrent))
            continue;

        // If hash set contains sqrtCurrent
        if (hashSet.find((int)sqrtCurrent) !=
            hashSet.end())
        {
            sum += (sqrtCurrent * sqrtCurrent);
        }
    }

    return sum;
}

// Driver code
int main()
{
    int arr[] = { 2, 4, 5, 6, 7, 8, 9, 3 };
    int n = sizeof(arr)/sizeof(arr[0]);
    cout << (getSum(arr, n));
    return 0;
}

// This code is contributed by Rajput-Ji

Java

// Java program to find the sum of all the elements
// from the array whose square root is present
// in the same array

import java.util.*;
public class GFG {

    // Function to return the required sum
    public static int getSum(int arr[], int n)
    {

        int i, sum = 0;

        // Initialization of hash map
        Set<Integer> hashSet = new HashSet<>();

        // Store each element in the hash map
        for (i = 0; i < n; i++)
            hashSet.add(arr[i]);

        for (i = 0; i < n; i++) {
            double sqrtCurrent = Math.sqrt(arr[i]);

            // If sqrtCurrent is a decimal number
            if (Math.floor(sqrtCurrent) != Math.ceil(sqrtCurrent))
                continue;

            // If hash set contains sqrtCurrent
            if (hashSet.contains((int)sqrtCurrent)) {
                sum += (sqrtCurrent * sqrtCurrent);
            }
        }

        return sum;
    }

    // Driver code
    public static void main(String args[])
    {
        int arr[] = { 2, 4, 5, 6, 7, 8, 9, 3 };
        int n = arr.length;
        System.out.println(getSum(arr, n));
    }
}

C#

// C# program to find the sum of all the elements
// from the array whose square root is present
// in the same array
using System;
using System.Collections.Generic;

class GFG
{

    // Function to return the required sum
    public static int getSum(int []arr, int n)
    {

        int i, sum = 0;

        // Initialization of hash map
        HashSet<int> hashSet = new HashSet<int>();

        // Store each element in the hash map
        for (i = 0; i < n; i++)
            hashSet.Add(arr[i]);

        for (i = 0; i < n; i++)
        {
            double sqrtCurrent = Math.Sqrt(arr[i]);

            // If sqrtCurrent is a decimal number
            if (Math.Floor(sqrtCurrent) !=
                Math.Ceiling(sqrtCurrent))
                continue;

            // If hash set contains sqrtCurrent
            if (hashSet.Contains((int)sqrtCurrent))
            {
                sum += (int)(sqrtCurrent * sqrtCurrent);
            }
        }

        return sum;
    }

    // Driver code
    public static void Main(String []args)
    {
        int []arr = { 2, 4, 5, 6, 7, 8, 9, 3 };
        int n = arr.Length;
        Console.WriteLine(getSum(arr, n));
    }
}

// This code contributed by Rajput-Ji

Python3

# Python3 program to find the sum of all the
# elements from the array whose square
# root is present in the same array
import math

# Function to return the required sum
def getSum(arr, n):
    sum = 0;

    # Initialization of hash map
    hashSet = set();

    # Store each element in the hash map
    for i in range(n):
        hashSet.add(arr[i]);

    for i in range(n):

        sqrtCurrent = math.sqrt(arr[i]);

        # If sqrtCurrent is a decimal number
        if (math.floor(sqrtCurrent) != math.ceil(sqrtCurrent)):
            continue;

        # If hash set contains sqrtCurrent
        if (int(sqrtCurrent) in hashSet):
            sum += int(sqrtCurrent * sqrtCurrent);

    return sum;

# Driver code
arr = [ 2, 4, 5, 6, 7, 8, 9, 3 ];
n = len(arr);
print(getSum(arr, n));

# This code is contributed by mits

PHP

<?php
// PHP program to find the sum of all the
// elements from the array whose square
// root is present in the same array

// Function to return the required sum
function getSum($arr, $n)
{
    $sum = 0;

    // Initialization of hash map
    $hashSet = array();

    // Store each element in the hash map
    for ($i = 0; $i < $n; $i++)
        array_push($hashSet, $arr[$i]);

    $hashSet = array_unique($hashSet);

    for ($i = 0; $i < $n; $i++)
    {
        $sqrtCurrent = sqrt($arr[$i]);

        // If sqrtCurrent is a decimal number
        if (floor($sqrtCurrent) != ceil($sqrtCurrent))
            continue;

        // If hash set contains sqrtCurrent
        if (in_array((int)$sqrtCurrent, $hashSet))
        {
            $sum += ($sqrtCurrent * $sqrtCurrent);
        }
    }

    return $sum;
}

// Driver code
$arr = array( 2, 4, 5, 6, 7, 8, 9, 3 );
$n = count($arr);
print(getSum($arr, $n));

// This code is contributed by mits
?>

Javascript

<script>

// Javascript program to find the sum of
// all the elements from the array whose
// square root is present in the same array

// Function to return the required sum
function getSum(arr, n)
{
    let i, sum = 0;

    // Initialization of hash map
    let hashSet = new Set();

    // Store each element in the hash map
    for(i = 0; i < n; i++)
        hashSet.add(arr[i]);

    for(i = 0; i < n; i++)
    {
        let sqrtCurrent = Math.sqrt(arr[i]);

        // If sqrtCurrent is a decimal number
        if (Math.floor(sqrtCurrent) !=
            Math.ceil(sqrtCurrent))
            continue;

        // If hash set contains sqrtCurrent
        if (hashSet.has(sqrtCurrent))
        {
            sum += (sqrtCurrent * sqrtCurrent);
        }
    }
    return sum;
}

// Driver code
let arr = [ 2, 4, 5, 6, 7, 8, 9, 3 ];
let n = arr.length;

document.write(getSum(arr, n));

// This code is contributed by unknown2108

</script>

Output

13

Complexity Analysis:

• Time Complexity: O(n)
• Auxiliary Space: O(n)