How to Delete an Element from a Set in C++?
Last Updated :
26 Feb, 2024
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A set in C++ is a container that stores unique elements in a sorted order. In this article, we will learn how to delete a specific element from a set.
Example:
Input: mySet = {5, 2, 8, 1, 4} Element to delete: 2 Output: mySet = {5, 1, 8, 4}
Delete an Element from a Set in C++
To delete a specific element from a std::set in C++, we can use the std::set::erase() function. This function removes all elements with a certain value from the set. We can also pass it to the iterator if we need.
C++ Program to Delete an Element from a Set in C++
// CPP program to delete an element from a Set
#include <iostream>
#include <set>
using namespace std;
// Driver Code
int main()
{
// Creating a set
set<int> mySet = { 1, 2, 3, 4, 5 };
// Printing elements before deletion
cout << "Elements before deletion: ";
for (int elem : mySet) {
cout << elem << " ";
}
cout << endl;
// Deleting element using iterators
auto it = mySet.find(3);
if (it != mySet.end()) {
mySet.erase(it);
}
// Printing elements after deletion
cout << "Elements after deletion using iterators: ";
for (int elem : mySet) {
cout << elem << " ";
}
cout << endl;
return 0;
}
// This code is contributed by Susobhan Akhuli
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// CPP program to delete an element from a Set2
3
4
using namespace std;5
6
// Driver Code7
int main()8
{9
// Creating a set10
set<int> mySet = { 1, 2, 3, 4, 5 };11
12
// Printing elements before deletion13
cout << "Elements before deletion: ";14
for (int elem : mySet) {15
cout << elem << " ";16
}17
cout << endl;18
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// Deleting element using iterators20
auto it = mySet.find(3);21
if (it != mySet.end()) {22
mySet.erase(it);23
}24
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// Printing elements after deletion26
cout << "Elements after deletion using iterators: ";27
for (int elem : mySet) {28
cout << elem << " ";29
}30
cout << endl;31
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return 0;33
}34
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// This code is contributed by Susobhan AkhuliOutput
Elements before deletion: 1 2 3 4 5 Elements after deletion using iterators: 1 2 4 5
Time Complexity: O(log N), where N is the number of elements in the set.
Auxiliary Space: O(1)
