C++ Algorithm

C++ Algorithm Library

In order to excel in the field of competitive programming having only knowledge about containers of STL is not enough and the programmers should be aware about the things that STL has to offer.

As a most popular library, STL possess a vast ocean of the algorithms that are generally for all the < algorithm > library functions.

Here is the list of the most widely used algorithms on vectors and that are known as the most useful in the Competitive Programming as depicted below:

Non-Manipulating Algorithms

Some Manipulating Algorithms

Example of C++ Algorithm

#include  
#include  
#include  
using namespace std; 
int main() 
{ 
	//intitalize vector array 
	int arr[] = {10,5,20,30,40,10,50,60}; 
	int num = sizeof(arr)/sizeof(arr[0]); 
	vector vect(arr, arr+num); 

	// Sort the given array
	sort(vect.begin(), vect.end()); 

	//it  Returns the first Position of 10 
	auto f = lower_bound(vect.begin(), vect.end(), 20); 

	//It  Returns the last Position of 10 
	auto l = upper_bound(vect.begin(), vect.end(), 20); 

	cout << "Here is the  lower bound position : "; 
	cout << f-vect.begin() << endl; 

	cout << "Here is the upper bound position: "; 
	cout << l-vect.begin() << endl; 

	return 0; 
}