Searching:
1:Linear Search
#include <iostream>
int linearSearch(int arr[], int size, int target) {
for (int i = 0; i < size; i++) {
if (arr[i] == target) {
return i;
}
}
return -1;
}
int main() {
int arr[] = {5, 3, 8, 4, 2};
int size = arr.size();
int target = 4;
int result = linearSearch(arr, size, target);
if (result != -1) {
std::cout << "Element found at index: " << result << endl;
} else {
std::cout << "Element not found in the array." << endl;
}
return 0;
}
2:Binary Search
#include <iostream>
int binarySearch(int arr[], int size, int target) {
int left = 0;
int right = size - 1;
while (left <= right) {
int mid = left + (right - left) / 2;
if (arr[mid] == target) {
return mid; }
else if (arr[mid] < target) {
left = mid + 1;
}
else {
right = mid - 1;
}
}
return -1;
}
int main() {
int arr[] = {2, 3, 4, 5, 8}; // Must be sorted for binary search
int size = sizeof(arr) );
int target = 5;
int result = binarySearch(arr, size, target);
if (result != -1) {
cout << "Element found at index: " << result << endl;
} else {
cout << "Element not found in the array." << endl;
}
return 0;
}
Sorting Techniques
1,Bubble Sort
#include <iostream>
void bubbleSort(int arr[], int size) {
for (int i = 0; i < size - 1; ++i) {
for (int j = 0; j < size - i - 1; ++j) {
if (arr[j] > arr[j + 1]) {
// Swap arr[j] and arr[j + 1]
int temp = arr[j];
arr[j] = arr[j + 1];
arr[j + 1] = temp;
}
}
}
}
int main() {
int arr[] = {64, 34, 25, 12, 22, 11, 90};
int size = sizeof(arr) ;
bubbleSort(arr, size);
:cout << "Sorted array: ";
for (int i = 0; i < size; ++i) {
std::cout << arr[i] << " ";
}
cout << endl;
return 0;
}
2,Selection Sort
#include <iostream>
void selectionSort(int arr[], int size) {
for (int i = 0; i < size - 1; ++i) {
int minIndex = i;
for (int j = i + 1; j < size; ++j) {
if (arr[j] < arr[minIndex]) {
minIndex = j;
}
}
// Swap arr[i] with arr[minIndex]
int temp = arr[i];
arr[i] = arr[minIndex];
arr[minIndex] = temp;
}
}
int main() {
int arr[] = {64, 25, 12, 22, 11};
int size = sizeof(arr[0]);
selectionSort(arr, size);
cout << "Sorted array: ";
for (int i = 0; i < size; ++i) {
cout << arr[i] << " ";
}
:cout << endl;
return 0;
}
3,Insertion Sort
#include <iostream>
void insertionSort(int arr[], int size) {
for (int i = 1; i < size; ++i) {
int key = arr[i];
int j = i - 1;
while (j >= 0 && arr[j] > key) {
arr[j + 1] = arr[j];
j = j - 1;
}
arr[j + 1] = key;
}
}
int main() {
int arr[] = {12, 11, 13, 5, 6};
int size = sizeof(arr) ;
insertionSort(arr, size);
std::cout << "Sorted array: ";
for (int i = 0; i < size; ++i) {
std::cout << arr[i] << " ";
}
cout << :endl;
return 0;
}
4,Quick sort
#include <iostream>
int partition(int arr[], int low, int high) {
int pivot = arr[high];
int i = low - 1;
for (int j = low; j < high; j++) {
if (arr[j] < pivot) {
i++;
int temp = arr[i];
arr[i] = arr[j];
arr[j] = temp;
}
}
int temp = arr[i + 1];
arr[i + 1] = arr[high];
arr[high] = temp;
return i + 1;
}
void quickSort(int arr[], int low, int high) {
if (low < high) {
int pi = partition(arr, low, high);
quickSort(arr, low, pi - 1);
quickSort(arr, pi + 1, high);
}
}
int main() {
int arr[] = {10, 7, 8, 9, 1, 5};
int size = sizeof(arr);
quickSort(arr, 0, size - 1);
cout << "Sorted array: ";
for (int i = 0; i < size; ++i) {
cout << arr[i] << " ";
}
cout <<endl;
return 0;
}
5,Merge Sort
#include <iostream>
void merge(int arr[], int left, int mid, int right) {
int n1 = mid - left + 1;
int n2 = right - mid;
int* leftArr = new int[n1];
int* rightArr = new int[n2];
for (int i = 0; i < n1; i++) {
leftArr[i] = arr[left + i];
}
for (int j = 0; j < n2; j++) {
rightArr[j] = arr[mid + 1 + j];
}
int i = 0, j = 0, k = left;
while (i < n1 && j < n2) {
if (leftArr[i] <= rightArr[j]) {
arr[k] = leftArr[i];
i++;
} else {
arr[k] = rightArr[j];
j++;
}
k++;
}
while (i < n1) {
arr[k] = leftArr[i];
i++;
k++;
}
while (j < n2) {
arr[k] = rightArr[j];
j++;
k++;
}
delete[] leftArr;
delete[] rightArr;
}
void mergeSort(int arr[], int left, int right) {
if (left < right) {
int mid = left + (right - left) / 2;
mergeSort(arr, left, mid);
mergeSort(arr, mid + 1, right);
merge(arr, left, mid, right);
}
}
int main() {
int arr[] = {38, 27, 43, 3, 9, 82, 10};
int size = sizeof(arr) / sizeof(arr[0]);
mergeSort(arr, 0, size - 1);
for (int i = 0; i < size; ++i) {
printf("%d ", arr[i]);
}
printf("\n");
return 0;
}
Binary Search Tree:
#include <iostream>
struct Node {
int data;
Node* left;
Node* right;
};
Node* createNode(int data) {
Node* newNode = new Node();
newNode->data = data;
newNode->left = nullptr;
newNode->right = nullptr;
return newNode;
}
Node* insert(Node* root, int data) {
if (root == nullptr) {
return createNode(data);
}
if (data < root->data) {
root->left = insert(root->left, data);
} else {
root->right = insert(root->right, data);
}
return root;
}
void inOrderTraversal(Node* root) {
if (root != nullptr) {
inOrderTraversal(root->left);
printf("%d ", root->data);
inOrderTraversal(root->right);
}
}
Node* search(Node* root, int data) {
if (root == nullptr || root->data == data) {
return root;
}
if (data < root->data) {
return search(root->left, data);
}
return search(root->right, data);
}
int main() {
Node* root = nullptr;
root = insert(root, 50);
insert(root, 30);
insert(root, 20);
insert(root, 40);
insert(root, 70);
insert(root, 60);
insert(root, 80);
printf("In-order traversal: ");
inOrderTraversal(root);
printf("\n");
int searchValue = 40;
Node* foundNode = search(root, searchValue);
if (foundNode != nullptr) {
printf("Node with value %d found.\n", searchValue);
} else {
printf("Node with value %d not found.\n", searchValue);
}
return 0;
}
