int on=1;
int off=1;
void setup() {
 // put your setup code here, to run once:
pinMode(13,OUTPUT);
Serial.begin(9600);
Serial.println("WELCOME TO ARDUINO LAB");
}
void loop() {
 // put your main code here, to run repeatedly:
digitalWrite(13,HIGH);
Serial.println(on);
on=on+1;
Serial.println("LED IS ON!");
delay(3000);
digitalWrite(13,LOW);
Serial.println(off);
off=off+1;
Serial.println("LED IS OFF");
delay(5000);
}