How many functions are defined in this program?

#include <iostream> 
#include <string>
using namespace std;

int addition (int, int );
int subtraction (int , int ); 
void directions();
void printResult(int , int , int , string);

int main ()
{   
    int x,y,r;   
    directions();    
    cout << "Please enter the first integer: ";    
    cin >> x;    
    cout << "Please enter the second integer: ";    
    cin >> y;  
    r = addition(x,y);  
    printResult(x,y,r,"+");
    r = subtraction(x,y);  
    printResult(x,y,r,"-");  
    system("pause");   
    return 0;
}

int addition (int a, int b)
{   
    int r;  
    r=a+b;   
    return (r);
} 

int subtraction (int a, int b)
{   
    int r;  
    r=a-b; 
    return (r);
}

void directions() 
{
    cout << "********************************************************" << endl << "Hello!" << endl
    << "This Program asks the user for two integers, then prints the sum and difference" << endl

    << "******************************************************" << endl << endl;
}

void printResult(int a, int b, int result, string operation)
{ 
    cout << a << " " << operation << " " << b << " = " << result << endl;
}