Queues in C++ are part of the Standard Template Library (STL). A queue is a linear data structure that follows the FIFO (First In, First Out) principle.<\/p>\n\n\n\n
A queue is a container where:<\/p>\n\n\n\n
Queues are useful because they:<\/p>\n\n\n\n
Think of a ticket counter:<\/p>\n\n\n\n
This is exactly how a queue works.<\/p>\n\n\n\n
To use queues in C++, include the Elements are added at the back of the queue.<\/p>\n\n\n\n Elements are removed from the front.<\/p>\n\n\n\n Queues are used in:<\/p>\n\n\n\n Queues are important because they:<\/p>\n\n\n\n Queues in C++ are simple yet powerful STL containers that follow the FIFO principle. They are widely used in real-world applications like scheduling, processing tasks, and algorithm design where order matters.<\/p>\n\n\n<queue><\/code> library.<\/p>\n\n\n\n#include <queue><\/code><\/pre>\n\n\n\nDeclaring a Queue<\/h1>\n\n\n\n
queue<int> q;<\/code><\/pre>\n\n\n\nAdding Elements (push)<\/h1>\n\n\n\n
q.push(10);
q.push(20);
q.push(30);<\/code><\/pre>\n\n\n\nRemoving Elements (pop)<\/h1>\n\n\n\n
q.pop();<\/code><\/pre>\n\n\n\nAccessing Elements<\/h1>\n\n\n\n
Front Element<\/h2>\n\n\n\n
cout << q.front();<\/code><\/pre>\n\n\n\nBack Element<\/h2>\n\n\n\n
cout << q.back();<\/code><\/pre>\n\n\n\nExample Program of Queue<\/h1>\n\n\n\n
#include <iostream>
#include <queue>
using namespace std;
int main() {
queue<int> q;
q.push(1);
q.push(2);
q.push(3);
cout << \"Front: \" << q.front() << endl;
cout << \"Back: \" << q.back() << endl;
q.pop();
cout << \"After pop, Front: \" << q.front() << endl;
return 0;
}<\/code><\/pre>\n\n\n\nOutput<\/h2>\n\n\n\n
Front: 1
Back: 3
After pop, Front: 2<\/code><\/pre>\n\n\n\nCommon Queue Functions<\/h1>\n\n\n\n
Function<\/th> Purpose<\/th><\/tr><\/thead> push()<\/code><\/td>Add element at back<\/td><\/tr> pop()<\/code><\/td>Remove front element<\/td><\/tr> front()<\/code><\/td>Access first element<\/td><\/tr> back()<\/code><\/td>Access last element<\/td><\/tr> size()<\/code><\/td>Get number of elements<\/td><\/tr> empty()<\/code><\/td>Check if queue is empty<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n How Queue Works<\/h1>\n\n\n\n
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Types of Queues<\/h1>\n\n\n\n
1. Simple Queue<\/h2>\n\n\n\n
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2. Circular Queue<\/h2>\n\n\n\n
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3. Priority Queue<\/h2>\n\n\n\n
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Difference Between Stack and Queue<\/h1>\n\n\n\n
Stack<\/th> Queue<\/th><\/tr><\/thead> LIFO (Last In First Out)<\/td> FIFO (First In First Out)<\/td><\/tr> Insert\/remove from top<\/td> Insert rear, remove front<\/td><\/tr> Used in recursion<\/td> Used in scheduling<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n Important Points About Queues<\/h1>\n\n\n\n
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Advantages of Queues<\/h1>\n\n\n\n
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Common Mistakes with Queues<\/h1>\n\n\n\n
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front()<\/code> on empty queue<\/li>\n\n\n\nReal-Life Applications<\/h1>\n\n\n\n
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Why Queues are Important<\/h1>\n\n\n\n
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Conclusion<\/h2>\n\n\n\n