gcd of two numbers in c++ inbuilt functions code example

Example 1: gcd of two numbers c++

// gcd function definition below:
int gcd(int a, int b) {
   if (b == 0)
   return a;
   return gcd(b, a % b);
}

int a = 105, b = 30;
cout<<"GCD of "<< a <<" and "<< b <<" is "<< gcd(a, b);
// output = "GCD of 105 and 30 is 15";

Example 2: c++ program for addition of two numbers using functions

#include <iostream>
using namespace std;

//function declaration
int addition(int a,int b);

int main()
{
	int a,b;	//to store numbers
	int add;	//to store addition 
	
	//read numbers
	cout<<"Enter first number: ";
	cin>>a;
	cout<<"Enter second number: ";
	cin>>b;
	
	//call function
	add=addition(a,b);
	
	//print addition
	cout<<"Addition is: "<<add<<endl;
	
	return 0;
}

//function definition
int addition(int a,int b)
{
	return (a+b);
}