C++ Exercises: Find the second smallest elements in a given array of integers

Last update on August 16 2025 12:56:02 (UTC/GMT +8 hours)

5. Second Smallest Element in Array

Write a C++ program to find the second smallest elements in a given array of integers.

Visual Presentation:

Pictorial Presentation: Find the second smallest elements in a given array of integers

Sample Solution:

C++ Code :

#include <iostream> // Header file for input/output stream
using namespace std; // Using the standard namespace

// Function to find the second smallest element in an array
int find_Second_Smallest(int array_num[], int n) {
  int smallest_num, second_smallest_num; // Declaring variables to store smallest and second smallest numbers

  // Determining initial smallest and second smallest numbers from the first two elements of the array
  if (array_num[0] < array_num[1]) {
    smallest_num = array_num[0];
    second_smallest_num = array_num[1];
  } else {
    smallest_num = array_num[1];
    second_smallest_num = array_num[0];
  }

  // Loop to find the second smallest number in the array
  for (int i = 0; i < n; i++) {
    // If current element is smaller than the smallest number
    if (smallest_num > array_num[i]) {
      second_smallest_num = smallest_num; // Assign the smallest number to second smallest
      smallest_num = array_num[i]; // Update the smallest number
    } 
    // If current element is greater than smallest but smaller than second smallest
    else if (array_num[i] < second_smallest_num && array_num[i] > smallest_num) {
      second_smallest_num = array_num[i]; // Update the second smallest number
    }
  }

  return second_smallest_num; // Return the second smallest number found
}

int main() {
  int n = 7; // Number of elements in the array
  int array_num[7] = {5, 6, 7, 2, 3, 4, 12}; // Declaration and initialization of an integer array
  int s = sizeof(array_num) / sizeof(array_num[0]); // Determining the size of the array

  cout << "Original array: "; // Output message indicating the original array is being displayed
  for (int i=0; i < s; i++)
    cout << array_num[i] <<" "; // Output each element of the array

  int second_smallest_num = find_Second_Smallest(array_num, n); // Finding the second smallest number in the array
  cout<<"\nSecond smallest number: "<<second_smallest_num; // Output the second smallest number found

  return 0;
}

Sample Output:

Original array: 5 6 7 2 3 4 12 
Second smallest number: 3

Flowchart:

For more Practice: Solve these Related Problems:

Write a C++ program to determine the second smallest element in an array by tracking the smallest and second smallest values.
Write a C++ program that sorts the array in ascending order and then selects the second unique smallest number.
Write a C++ program to scan an array and update two variables to capture the minimum and second minimum values simultaneously.
Write a C++ program that reads an array and prints the second smallest element while handling duplicate minimums appropriately.

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