All DSA Problems

Author: alisamad1

.gitignore

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+# Ignore Visual Studio Code specific files
+.vscode/
+
+# Ignore compiled executables and object files
+*.exe
+*.out
+*.o
+
+# Ignore temporary files created by VS Code extensions
+tempCodeRunnerFile.cpp

Graph/BFS.cpp

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+#include<iostream>
+#include<vector>
+#include<queue>
+using namespace std;
+vector<int>bfs_of_graph(vector<vector<int>>& adj, int V){
+    vector<int> ans;
+    vector<int> vis(V,0);
+    queue<int> q;
+    q.push(0);
+    vis[0] = 1;
+    while(!q.empty()){
+        int curr = q.front();
+        q.pop();
+        vis[curr] = 1;
+        ans.push_back(curr);
+        for(auto & it : adj[curr]){
+            if(vis[it] == 0){
+                vis[it] = 1;
+                q.push(it);
+            }
+        }
+    }
+    return ans;
+}
+int main(){
+    int V = 5;
+    vector<vector<int>> adj(V);
+    adj[0] = {1,2};
+    adj[1] = {0,3};
+    adj[2] = {0,4};
+    adj[3] = {1};
+    adj[4] = {2};
+    vector<int> result = bfs_of_graph(adj,V);
+    cout <<"BFS Traversal: " ;
+    for(int node : result){
+        cout << node << " ";
+    }
+    cout << endl;
+    return 0;
+}

Graph/DFS.cpp

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+#include<iostream>
+#include<vector>
+using namespace std;
+void dfs(vector<int>& ans, vector<int>& vis, int node, vector<int> adj[]){
+    vis[node] = 1;
+    ans.push_back(node);
+    for(auto &it : adj[node]){
+        if(vis[it]){
+            vis[it] = 1;
+            dfs(ans,vis, it, adj);
+        }
+    }
+}
+vector<int> dfs_of_graph(int V, vector<int> adj[]){
+    vector<int> ans;
+    vector<int> vis(V, 0);
+    for(int i = 0 ; i < V ; i++){
+        if(vis[0] == 0){
+            dfs(ans, vis, i adj);
+        }
+    }
+    return ans;
+}
+int main() {
+    int V = 5;
+    vector<int> adj[V];
+    adj[0].push_back(1);
+    adj[0].push_back(2);
+    adj[1].push_back(0);
+    adj[1].push_back(4);
+    adj[2].push_back(0);
+    adj[2].push_back(3);
+    adj[3].push_back(2);
+    adj[4].push_back(1);
+    vector<int> result = dfs_of_graph(adj, V);
+    cout << "DFS Traversal: ";
+    for(auto node : result) {
+        cout << node << " ";
+    }
+    cout << endl;
+    return 0;
+}

Leetcode_Practice_Questions

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+Subproject commit 27cd74f977317b55a93b5512ee1cb5f3b8492f72

Linked_List

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+Subproject commit 99fea4f0db9a702e089a605394af7b8398bde0e2

README.md

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+<<<<<<< HEAD
+# C++ Data Structures & Algorithms (DSA) + LeetCode Solutions
+
+![Language](https://img.shields.io/badge/Language-C%2B%2B-blue.svg)
+![License](https://img.shields.io/badge/License-MIT-green.svg)
+![Repo Status](https://img.shields.io/badge/Status-Active-brightgreen.svg)
+
+Welcome to **C++ DSA & LeetCode Solutions**—your all-in-one resource for mastering data structures, algorithms and acing coding interviews!  
+Welcome to **C++ DSA & LeetCode Solutions**—your all-in-one resource for mastering data structures, algorithms and acing coding interviews!
+This repository features clean, well-documented C++ implementations covering foundational CS concepts *and* a growing library of LeetCode problem solutions.
+
+---
+
+## 🚩 Features
+
+- **Core DSA modules:** Binary search, sorting, arrays, and more.
+- **Extensive LeetCode practice:** Solutions mapped by problem number, ideal for interviews and self-study.
+- **Clear folder structure:** Easily find what you need, whether it’s theory or practice.
+- **Beginner-friendly:** Accessible explanations and simple build instructions.
+
+---
+
+## 📁 Repository Structure
+
+DSA/
+├── Leetcode_Practice_Questions/ # LeetCode solutions
+│ ├── LC_1.cpp
+│ ├── LC_2.cpp
+│ └── README.md
+├── binarysearch.cpp # Core algorithms/data structures
+├── sort_0_&_1.cpp
+├── ...
+└── README.md # Start here!
+
+```
+cppdsa/
+├── Leetcode_Practice_Questions/  # LeetCode solutions
+│   ├── LC_1.cpp
+│   ├── LC_2.cpp
+│   └── ...
+├── binarysearch.cpp              # Core algorithms/data structures
+├── sort_0_&_1.cpp
+└── README.md                     # Start here!
+```
+
+### Highlights
+
+- **Leetcode_Practice_Questions**:  
+- **Leetcode_Practice_Questions**:
+  Organized, numbered solutions with a focused [README](./Leetcode_Practice_Questions/README.md).
+
+- **Core DSA files**:  
+  Example:  
+  - `binarysearch.cpp`: Classic binary search implementation  
+  - `sort_0_&_1.cpp`: Fast 0/1 segregation in arrays  
+- **Core DSA files**:
+  Example:
+  - `binarysearch.cpp`: Classic binary search implementation
+  - `sort_0_&_1.cpp`: Fast 0/1 segregation in arrays
+  - (More coming soon!)
+
+---
+
+## 🧑‍💻 Usage & Getting Started
+
+1. **Clone the Repository**
+git clone https://github.com/alisamad1/DSA.git
+   ```bash
+   git clone https://github.com/your-username/your-repo-name.git
+   ```
+2. **Enter the Directory**
+cd DSA
+   ```bash
+   cd cppdsa
+   ```
+3. **Compile & Run Any File**
+- With `g++` (example for binarysearch):
+  ```
+  g++ binarysearch.cpp -o binarysearch
+  ./binarysearch
+  ```
+   ```bash
+   g++ binarysearch.cpp -o binarysearch
+   ./binarysearch
+   ```
+- Or open files using your favorite C++ IDE (e.g., VS Code, CLion).
+
+---
+
+## ✍️ Contributing
+
+Contributions, bug reports, and suggestions are welcome!  
+Whether you spot a typo, want to add a new algorithm, or have ideas for improvement, just open an issue or pull request.
+Contributions, bug reports, and suggestions are welcome!
+Whether you spot a typo, want to add a new algorithm, or have ideas for improvement, just open an issue or pull request on the new repository.
+
+---
+
+## 💡 Why Use This Repository?
+
+- **Exam & Interview Prep:** Spot-on for students and job-seekers.
+- **Learning by Examples:** Study code, understand logic, and solve problems hands-on.
+- **Open Source:** Freely use and extend under the MIT License.
+
+---
+
+## 📫 Contact
+
+Questions? Ideas?  
+Questions? Ideas?
+Let’s connect!
+
+- **LinkedIn:** Ali Us Samad  
+- **LinkedIn:** Ali Us Samad
+- **Email:** aliussamad@gmail.com
+
+---
+
+## ⭐ Support
+
+If this project helps you, please ⭐️ this repo and share it to support more learners!

Recursion

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+Subproject commit 73b3106f285e245aad37f9fde24ff69e1e8aced2

Stack&Queues/Problem_1.cpp

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+//Implementation of Stack Using Linked List in C++
+#include<iostream>
+using namespace std;
+struct Node{
+    int data;
+    Node* next;
+}
+Node * top;
+void push(int data){
+    Node * temp = new Node();
+    if(!temp){
+        cout<<"Stack Overflow"<<endl;
+    }
+    temp -> data = data;
+    temp -> next = top;
+    temp = top;
+}
+int isEmpty(){
+    return top == NULL;
+}
+int peek(){
+    if(!isEmpty()){
+        return top->data;
+    }
+    else{
+        exit(1);
+    }
+}
+void pop(){
+    Node * temp;
+    if(top == NULL){
+        cout<<"Stack Underflow"<<endl;
+        exit(1);
+    }
+    else{
+        temp = top;
+        top = top->next;
+        free(top);
+    }
+}

Stack&Queues/Problem_2.cpp

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+// Implementation of Queues using Linked List
+#include<iostream>
+using namespace std;
+class Node{
+    // node class for queue
+public:
+       int data;
+       Node* next;
+       //constructor 
+       Node(int data){
+        this->data = data;
+        this->next = NULL;
+       }
+};
+class Queue{
+    private:
+    Node *rear,*front;
+    public:
+    Queue(){
+        front = rear = NULL;
+    }
+    void Enqueue(int x){
+        Node* temp = new Node(x);
+        if(rear == NULL){
+            front = rear = temp;
+            return;
+        }
+        rear->next = temp;
+        rear = temp;
+    }
+    void deQueue(){
+        if(front == NULL){
+            cout<<"Queue is Empty"<<endl;
+            return;
+        }
+        Node* OldFront = front;
+        Node = front->next;
+        if(front == NULL){
+            rear = NULL;
+        }
+        delete OldFront;
+    }
+    void display(){
+        if(front == NULL){
+            cout<<"queue is empty"<<endl;
+            return;
+        }
+        Node* temp = front;
+        while(temp!=NULL){
+            cout<<temp->data<<" ";
+            temp = temp->next;
+        }
+        cout<<endl;
+    }
+};
+int main(){
+    Queue q;
+    q.Enqueue(10);
+    q.Enqueue(20);
+    q.Enqueue(30);
+    cout<<"Queue after EnQueue operations: "<<endl;
+    q.display();
+    q.deQueue();
+    q.display();
+    return 0;
+}

Stack&Queues/Problem_3.cpp

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+//implentation of stack using queue
+#include<iostream>
+#include<queue>
+using namespace std;
+class MyStack {
+    queue<int>q;
+    public: 
+    void push(int x){
+        q.push(x);
+        int n = q.size();
+        for(int i = 0; i<n-1; i++){
+            int value = q.front();
+            q.pop();
+            q.push(value);
+        }
+    }
+    int pop(){
+        if(q.empty()){
+            cout<<"stack underflow. No elements to pop out"<<endl;
+            return -1;
+        }
+        int value = q.front();
+        q.pop();
+        return value;
+    }
+    int top(){
+        if(q.empty()){
+            cout<<"Stack Underflow. No elements to pop out"<<endl;
+            return -1;
+        }
+        return q.front();
+    }
+    int size(){
+        return q.size();
+    }
+    bool isEmpty(){
+        return q.empty();
+    }
+};
+int main(){
+    MyStack s;
+    s.push(10);
+    s.push(20);
+    s.push(30);
+    cout<<"Stack top "<<s.top()<<endl;
+    cout<<"Stack Size "<<s.size()<<endl;
+    cout<<"Popped Element "<<s.pop()<<endl;
+    cout<<"Stack top after popping element "<<s.top()<<endl;
+    return 0;
+}