How to python set in C++

In Python, a set is an unordered collection of unique elements. The set() function is used to create a new set object. It takes an iterable object as an argument and returns a set containing all the unique elements from the iterable. If no argument is passed, an empty set is returned. Sets are mutable, meaning that you can add or remove elements from them. Some common operations that can be performed on sets include union, intersection, difference, and symmetric difference. Sets are useful for removing duplicates from a list, checking for membership, and performing mathematical operations on collections of elements. Keep reading below to learn how to python set in C++.

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Python ‘set’ in C++ With Example Code

Python sets are a powerful data structure that allow for efficient storage and manipulation of unique elements. While C++ does not have a built-in set data type, it is possible to implement a set using a variety of techniques.

One common approach is to use a hash table to store the elements of the set. This involves creating a custom hash function that maps each element to a unique index in the table. When adding an element to the set, the hash function is used to determine its index in the table. If there is already an element at that index, the new element is added to a linked list at that index. When checking if an element is in the set, the hash function is used to determine its index and then the linked list at that index is searched for the element.

Here is an example implementation of a set in C++ using a hash table:

“`
#include
#include

class Set {
public:
Set() {
table.resize(100);
}

void add(int x) {
int index = hash(x);
for (int element : table[index]) {
if (element == x) {
return;
}
}
table[index].push_back(x);
}

bool contains(int x) {
int index = hash(x);
for (int element : table[index]) {
if (element == x) {
return true;
}
}
return false;
}

private:
std::vector> table;

int hash(int x) {
return x % table.size();
}
};

int main() {
Set s;
s.add(1);
s.add(2);
s.add(3);
std::cout << s.contains(2) << std::endl; // prints 1 (true) std::cout << s.contains(4) << std::endl; // prints 0 (false) return 0; } ``` In this implementation, the hash function simply takes the modulus of the element with the size of the table. This is a simple hash function that works well for small sets. For larger sets, a more complex hash function may be needed to avoid collisions. Overall, implementing a set in C++ using a hash table is a powerful technique that can be used to efficiently store and manipulate unique elements.

Equivalent of Python set in C++

In conclusion, the equivalent function of Python’s set() in C++ is the unordered_set. Both set() and unordered_set are used to store unique elements in a collection. However, the main difference between the two is that set() stores elements in a sorted order while unordered_set stores elements in an unordered manner. The unordered_set function in C++ provides a fast and efficient way to store and access unique elements in a collection. It also offers a variety of useful functions such as insert(), erase(), and find() that make it easy to manipulate the elements in the set. Overall, if you are looking for a way to store unique elements in C++, the unordered_set function is a great option to consider. It provides similar functionality to Python’s set() and is a valuable tool for any C++ programmer.