unsigned long start, finished, elapsed;

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

void displayResult(){
float h,m,s,ms;
unsigned long over;
elapsed=finished-start;
h=int(elapsed/3600000);
over=elapsed%3600000;
m=int(over/60000);
over=over%60000;
s=int(over/1000);
ms=over%1000;
Serial.print("Raw elapsed time: ");
Serial.println(elapsed);
Serial.print("Elapsed time: ");
Serial.print(h,0);
Serial.print("h ");
Serial.print(m,0);
Serial.print("m ");
Serial.print(s,0);
Serial.print("s ");
Serial.println("ms");
Serial.println();
}

void loop(){
finished=millis();
delay(10);
displayResult();
}

اینجا من ساده ترش کردم واست