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

extern"C"{
  int add_three(void);
}
void myPrint(char *fnName,unsigned int result);
void setup()
{
  Serial.begin(9600);
}

void loop()
{
  int result;
  result = add_three();
  myPrint("add_three",result);

}

void myPrint(char *fnName,unsigned int printVal){
  Serial.print("The sum of 10 +20+30");
  Serial.print(fnName);
  Serial.print(":");
  Serial.print(printVal);
}