Hello, coder army! In this lecture, we will dive into some array-related questions to enhance our hands-on practice. We will also explore how to pass arrays to functions. Without further ado, let's get started! ## Searching for an Element in an Array ### Problem Statement Given an array, we need to search for a specific element and return its index if present. If the element is not found, we will return -1. ### Example Consider the array: `arr = [10, 20, 11, 8, 4]`. If we want to find the element `11`, we will check each element sequentially: - Is `11` equal to `10`? No. - Is `11` equal to `20`? No. - Is `11` equal to `11`? Yes! Return index `2`. If we search for `18`, we will check all elements and find that it is not present, thus returning -1. ### Logic Implementation To implement this, we can use a loop to iterate through the array: ```cpp int searchElement(int arr[], int n, int x) { for (int i = 0; i < n; i++) { if (arr[i] == x) { return i; // Element found } } return -1; // Element not found } ``` ## Reversing an Array ### Problem Statement The task is to reverse the elements of a given array. ### Example For the array `arr = [9, 8, 4, 7, 11, 6]`, the reversed array should be `[6, 11, 7, 4, 8, 9]`. ### Logic Implementation We can create a new array to store the reversed elements: ```cpp void reverseArray(int arr[], int n) { int temp[n]; for (int i = 0; i < n; i++) { temp[i] = arr[n - 1 - i]; } for (int i = 0; i < n; i++) { arr[i] = temp[i]; } } ``` Alternatively, we can reverse the array in place without using extra space: ```cpp void reverseArrayInPlace(int arr[], int n) { int start = 0, end = n - 1; while (start < end) { swap(arr[start], arr[end]); start++; end--; } } ``` ## Finding the Second Maximum Element ### Problem Statement Given an array, find the second largest distinct element. ### Example For the array `arr = [12, 35, 1, 10, 34]`, the second largest element is `34`. ### Logic Implementation To find the second largest element, we can first find the maximum and then search for the next largest: ```cpp int findSecondMax(int arr[], int n) { int max = INT_MIN, secondMax = INT_MIN; for (int i = 0; i < n; i++) { if (arr[i] > max) { secondMax = max; max = arr[i]; } else if (arr[i] > secondMax && arr[i] != max) { secondMax = arr[i]; } } return secondMax; } ``` ## Using Functions with Arrays ### Passing Arrays to Functions To pass an array to a function, we can simply use the array name and its size as parameters: ```cpp void printArray(int arr[], int size) { for (int i = 0; i < size; i++) { cout << arr[i] << " "; } } ``` ### Example of Function Call ```cpp int main() { int arr[5] = {1, 2, 3, 4, 5}; printArray(arr, 5); return 0; } ``` ## Conclusion In this lecture, we covered various techniques for solving array-related problems, including searching for elements, reversing arrays, and finding maximum values. We also learned how to pass arrays to functions effectively. I hope you found this lecture helpful and engaging. If you enjoyed it, please like and share! See you in the next lecture!