Smallest Pair Sum in an array

Last Updated : 16 Apr, 2024

Given an array of distinct integers arr[], the task is to find a pair which has the minimum sum and print the sum.

Examples:

Input: arr[] = {1, 2, 3}
Output: 3
The pair (1, 2) will have the minimum sum pair i.e. 1 + 2 = 3

Input: arr[] = {3, 5, 6, 2}
Output: 5

Approach:

Find the minimum element from the array and store it in min.
Find the second minimum element from the array and store it in secondMin.
Print min + secondMin.

Below is the implementation of the above approach:

C++

// C++ program to print the sum of the minimum pair
#include <bits/stdc++.h>
using namespace std;

// Function to return the sum of
// the minimum pair from the array
int smallest_pair(int a[], int n)
{
    int min = INT_MAX, secondMin = INT_MAX;
    for (int j = 0; j < n; j++) {

        // If found new minimum
        if (a[j] < min) {

            // Minimum now becomes second minimum
            secondMin = min;

            // Update minimum
            min = a[j];
        }

        // If current element is > min and < secondMin
        else if (a[j] < secondMin)

            // Update secondMin
            secondMin = a[j];
    }

    // Return the sum of the minimum pair
    return (secondMin + min);
}

// Driver code
int main()
{
    int arr[] = { 1, 2, 3 };
    int n = sizeof(arr) / sizeof(arr[0]);

    cout << smallest_pair(arr, n);

    return 0;
}

Java

// Java program to print the sum 
// of the minimum pair
import java .io.*;

class GFG
{
// Function to return the sum of
// the minimum pair from the array
static int smallest_pair(int[] a, int n)
{
    int min =  Integer.MAX_VALUE, secondMin =  Integer.MAX_VALUE;
    for (int j = 0; j < n; j++) 
    {

        // If found new minimum
        if (a[j] < min)
        {

            // Minimum now becomes second minimum
            secondMin = min;

            // Update minimum
            min = a[j];
        }

        // If current element is > min and < secondMin
        else if ((a[j] < secondMin) && a[j] != min)

            // Update secondMin
            secondMin = a[j];
    }

    // Return the sum of the minimum pair
    return (secondMin + min);
}

// Driver code
public static void main(String[] args)
{
    int[] arr = { 1, 2, 3 };
    int n = arr.length;

    System.out.println(smallest_pair(arr, n));
}
}

// This code is contributed 
// by inder_verma

Python3

# Python3 program to print the 
# sum of the minimum pair 
import sys

# Function to return the sum of 
# the minimum pair from the array 
def smallest_pair(a, n) :
    
    min = sys.maxsize
    secondMin = sys.maxsize
    
    for j in range(n) : 

        # If found new minimum 
        if (a[j] < min) :

            # Minimum now becomes 
            # second minimum 
            secondMin = min

            # Update minimum 
            min = a[j]
        
        # If current element is > min 
        # and < secondMin 
        elif ((a[j] < secondMin) and 
               a[j] != min) :

            # Update secondMin 
            secondMin = a[j] 
    
    # Return the sum of the minimum pair 
    return (secondMin + min)

# Driver code 
if __name__ == "__main__" : 

    arr = [ 1, 2, 3 ] 
    n = len(arr) 

    print(smallest_pair(arr, n)) 

# This code is contributed by Ryuga

// C# program to print the sum 
// of the minimum pair
using System;

class GFG
{
// Function to return the sum of
// the minimum pair from the array
static int smallest_pair(int[] a, int n)
{
    int min = int.MaxValue, secondMin = int.MaxValue;
    for (int j = 0; j < n; j++) 
    {

        // If found new minimum
        if (a[j] < min)
        {

            // Minimum now becomes second minimum
            secondMin = min;

            // Update minimum
            min = a[j];
        }

        // If current element is > min and < secondMin
        else if ((a[j] < secondMin) && a[j] != min)

            // Update secondMin
            secondMin = a[j];
    }

    // Return the sum of the minimum pair
    return (secondMin + min);
}

// Driver code
public static void Main()
{
    int[] arr = { 1, 2, 3 };
    int n = arr.Length;

    Console.Write(smallest_pair(arr, n));
}
}

// This code is contributed 
// by Akanksha Rai

JavaScript

<script>

    // Javascript program to print the sum 
    // of the minimum pair
    
    // Function to return the sum of
    // the minimum pair from the array
    function smallest_pair(a, n)
    {
        let min = Number.MAX_VALUE, 
        secondMin = Number.MAX_VALUE;
        for (let j = 0; j < n; j++) 
        {

            // If found new minimum
            if (a[j] < min)
            {

                // Minimum now becomes second minimum
                secondMin = min;

                // Update minimum
                min = a[j];
            }

            // If current element is > min
            // and < secondMin
            else if ((a[j] < secondMin) && 
                      a[j] != min)

                // Update secondMin
                secondMin = a[j];
        }

        // Return the sum of the minimum pair
        return (secondMin + min);
    }
    
    let arr = [ 1, 2, 3 ];
    let n = arr.length;
  
    document.write(smallest_pair(arr, n));
    
</script>

PHP

<?php
// PHP program to print the sum 
// of the minimum pair 

// Function to return the sum of 
// the minimum pair from the array 
function smallest_pair($a, $n) 
{ 
    $min = PHP_INT_MAX;
    $secondMin = PHP_INT_MAX; 
    for ($j = 0; $j < $n; $j++) 
    { 

        // If found new minimum 
        if ($a[$j] < $min) 
        { 

            // Minimum now becomes 
            // second minimum 
            $secondMin = $min; 

            // Update minimum 
            $min = $a[$j]; 
        } 

        // If current element is > min 
        // and < secondMin 
        else if (($a[$j] < $secondMin) &&
                  $a[$j] != $min) 

            // Update secondMin 
            $secondMin = $a[$j]; 
    } 

    // Return the sum of the minimum pair 
    return ($secondMin + $min); 
} 

// Driver code 
$arr = array( 1, 2, 3 ); 
$n = sizeof($arr); 
echo smallest_pair($arr, $n); 

// This code is contributed by ajit
?>

Output

Complexity Analysis:

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

Smallest Pair Sum in an array

Devyansh_Ojha

Improve

Article Tags :

Practice Tags :

Smallest Pair Sum in an array

Similar Reads

Thank You!

What kind of Experience do you want to share?