Data Structures - Using C++ Standard Library

The C++ Standard Library provides a rich set of data structures and algorithms that simplify the implementation of various data structures. In this guide, we'll explore some of the commonly used data structures provided by the C++ Standard Library, along with sample code and explanations.

1. Vectors

A vector is a dynamic array that can grow in size as needed. It is part of the Standard Library's sequence container. Here's how you can use vectors in C++:

#include <iostream>
#include <vector>
int main() {
    std::vector<int> myVector;    // Add elements to the vector
    myVector.push_back(1);
    myVector.push_back(2);
    myVector.push_back(3);
    // Access elements
    std::cout << "Vector Elements:" << std::endl;
    for (int element : myVector) {
        std::cout << element << " ";
    }
    std::cout << std::endl;
    return 0;
}
    

2. Maps

A map is an associative container that stores key-value pairs. It allows for efficient lookup based on keys. Here's an example of using maps in C++:

#include <iostream>
#include <map>
#include <string>
int main() {
    std::map<std::string, int> myMap;    // Add key-value pairs to the map
    myMap["Alice"] = 25;
    myMap["Bob"] = 30;
    myMap["Charlie"] = 28;
    // Access values by key
    std::cout << "Age of Bob: " << myMap["Bob"] << std::endl;
    return 0;
}
    

3. Sets

A set is an associative container that stores unique values. It is useful for maintaining collections of unique elements. Here's an example of using sets in C++:

#include <iostream>
#include <set>
int main() {
    std::set<int> mySet;    // Add elements to the set
    mySet.insert(3);
    mySet.insert(1);
    mySet.insert(2);
    // Access elements (they are automatically sorted)
    std::cout << "Set Elements:" << std::endl;
    for (int element : mySet) {
        std::cout << element << " ";
    }
    std::cout << std::endl;
    return 0;
}
    

4. Queues and Stacks

The Standard Library provides queue and stack containers. They are often used for implementing queues and stacks in C++:

#include <iostream>
#include <queue>
#include <stack>
int main() {
    std::queue<int> myQueue;
    std::stack<int> myStack;
    // Queue operations
    myQueue.push(1);
    myQueue.push(2);
    int frontElement = myQueue.front();
    myQueue.pop();
    // Stack operations
    myStack.push(1);
    myStack.push(2);
    int topElement = myStack.top();
    myStack.pop();
    return 0;
}
    

5. Conclusion

The C++ Standard Library provides a powerful set of data structures and algorithms that can simplify your programming tasks. By using vectors, maps, sets, queues, and stacks, you can efficiently manage and manipulate data in your C++ programs.