C program to find the second largest element in an array using bubble sort

🔹 Find Second Largest Element in Array (C Program)

#include <stdio.h>

void secondLargest(int a[], int num)
{
    // Bubble sort the array in ascending order
    for(int i = 0; i < num - 1; i++)
    {
        for(int j = 0; j < num - i - 1; j++)
        {
            if(a[j] > a[j+1])
            {
                int temp = a[j];
                a[j] = a[j+1];
                a[j+1] = temp;
            }
        }
    }

    // After sorting, the second largest element will be at index num-2
    printf("Second largest element in the array: %d\n", a[num - 2]);
}

int main()
{
    int num;
    printf("Enter the size of the array:\n");
    scanf("%d", &num);

    if(num < 2)
    {
        printf("Invalid! Need at least 2 numbers to find the second largest element.\n");
        return 1;
    }

    int a[num];
    printf("Enter %d elements:\n", num);
    for(int i = 0; i < num; i++)
    {
        scanf("%d", &a[i]);
    }

    secondLargest(a, num);
    return 0;
}
  

📘 Explanation:

• Reads the size and elements of the array.
• Sorts the array using Bubble Sort in ascending order.
• The second largest number will be at index num - 2 after sorting.
• Checks for at least 2 elements as a requirement.

🧪 Sample Output:

Enter the size of the array:
5
Enter 5 elements:
3 8 2 7 4
Second largest element in the array: 7
    

🏷️ Keywords:

second largest in C, array sorting, C program for array, bubble sort, C beginner exercise, top two elements