Example: Find Second Largest Element (Two-Pass Scan) in C

// Find Second Largest Element (Two-Pass Scan)
#include <stdio.h>
#include <limits.h> // For INT_MIN

int main() {
    int arr[] = {12, 35, 1, 10, 34, 1};
    int n = sizeof(arr) / sizeof(arr[0]);

    if (n < 2) {
        printf("Array must have at least two elements.\n");
        return 0;
    }

    // Step 1: Find the largest element
    int largest = INT_MIN;
    for (int i = 0; i < n; i++) {
        if (arr[i] > largest) {
            largest = arr[i];
        }
    }

    // Step 2: Find the second largest element
    // Initialize secondLargest to a very small number or a sentinel
    int secondLargest = INT_MIN;
    for (int i = 0; i < n; i++) {
        if (arr[i] > secondLargest && arr[i] < largest) {
            secondLargest = arr[i];
        }
    }

    if (secondLargest == INT_MIN) {
        printf("No second distinct largest element found.\n");
    } else {
        printf("The second largest element is: %d\n", secondLargest);
    }

    return 0;
}