#include<stdio.h>
#include<stdlib.h>

extern"C"{
  int add_three(void);
}

void setup()
{
  Serial.begin(9600);
}

void loop()
{
  int result;
  result = add_three();
  Serial.print("The sum of three numbers is: ");
  Serial.println(result);
  delay(1000); // Delay for 1 second

}