Understanding Sets
- Computer Science Department
Understanding set in C++
What is set?
set is an associative container in the C++ Standard Library that stores unique elements following a specific order. It is implemented as a balanced binary search tree, typically a Red-Black tree. Sets provide fast retrieval, insertion, and deletion of elements.
Why Use set?
Uniqueness: Ensures all elements are unique.
Ordered Elements: Automatically keeps elements sorted.
Efficiency: Provides logarithmic time complexity for search, insert, and delete operations.
Syntax
Here's the basic syntax for creating a std::set:
#include <set>
using namespace std;
set<ElementType> setName;ElementType: The type of elements stored in the set.setName: The name of the set object.
Common set Functions
insert
Description: Inserts an element into the set.
Syntax:
pair<iterator, bool> insert(const value_type& value);Example:
#include <iostream>
#include <set>
using namespace std;
int main() {
set<int> mySet;
mySet.insert(10);
mySet.insert(20);
mySet.insert(10); // Duplicate, will not be inserted
for (const int& val : mySet) {
cout << val << " ";
}
cout << endl;
return 0;
}find
Description: Finds an element in the set.
Syntax:
Example:
erase
Description: Removes elements from the set.
Syntax:
Example:
size
Description: Returns the number of elements in the set.
Syntax:
Example:
clear
Description: Removes all elements from the set.
Syntax:
Example:
begin and end
Description: Returns an iterator to the beginning or end of the set.
Syntax:
Example:
2024 - Programming 3 / Data Structures - Author: Dr. Kevin Roark