C Exercises: Find two elements whose sum is closest to zero

Last update on March 18 2025 13:23:38 (UTC/GMT +8 hours)

45. Two Elements Sum Closest to Zero

Write a program in C to find two elements whose sum is closest to zero.

The task is to find two elements in an array whose sum is closest to zero. The program will iterate through the array, checking pairs of elements, and determine the pair with the smallest absolute sum, then print those elements.

Visual Presentation:

C Exercises: Find two elements whose sum is closest to zero

Sample Solution:

C Code:

#include <stdio.h>
#include <math.h>
#include <stdlib.h>

// Function to find and display the pair of elements whose sum is minimum
void findMinSumPair(int *arr1, int arr_size) {
    int i, j, sum, minSum, min1Pair, min2Pair;

    // Check for valid input array
    if (arr1 == NULL || arr_size < 2)
        return;

    // Initialize variables to track minimum sum and respective pair elements
    min1Pair = arr1[0];
    min2Pair = arr1[1];
    minSum = min1Pair + min2Pair;

    // Iterate through the array to find the pair with the minimum sum
    for (i = 0; i < arr_size - 1; i++) {
        for (j = i + 1; j < arr_size; j++) {
            sum = arr1[i] + arr1[j];
            // Update minimum sum and pair elements if the current sum is smaller
            if (abs(sum) < abs(minSum)) {
                minSum = sum;
                min1Pair = arr1[i];
                min2Pair = arr1[j];
            }
        }
    }
    // Print the pair of elements whose sum is minimum
    printf("[%d, %d]\n", min1Pair, min2Pair);
}

int main() {
    int arr1[] = {38, 44, 63, -51, -35, 19, 84, -69, 4, -46}; 
    int ctr = sizeof(arr1) / sizeof(arr1[0]);
    int i;  

    // Print the original array
    printf("The given array is :  ");
    for (i = 0; i < ctr; i++) {
        printf("%d  ", arr1[i]);
    } 
    printf("\n");

    // Find and display the pair of elements whose sum is minimum
    printf("The Pair of elements whose sum is minimum are: \n");
    findMinSumPair(arr1, ctr);
    return 0;
}

Sample Output:

The given array is :  38  44  63  -51  -35  19  84  -69  4  -46  
The Pair of elements whose sum is minimum are: 
[44, -46]

Flowchart:

For more Practice: Solve these Related Problems:

Write a C program to find two elements in an array whose sum is closest to zero using sorting and two-pointer technique.
Write a C program to identify the pair with the minimum absolute sum using nested loops and compare differences.
Write a C program to find the pair of elements with the closest sum to zero using recursion.
Write a C program to compute the pair with the sum closest to zero and then output the absolute difference of that sum.

C Programming Code Editor:

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