//mengenalkan bahan yang digunakan
int led1 = 3;
int led2 = 2;
int led3 = 1;
int pb1 = 4;

//mengenalkan pin yang digunakan 
void setup() {
 pinMode(3, OUTPUT);
 pinMode(2, OUTPUT);
 pinMode(1, OUTPUT);
 pinMode(4, INPUT);
}
void loop() {
//menekan saklar akan menyalakan led
 if(digitalRead(4)==HIGH)
 {
 digitalWrite(3, HIGH);
 delay(100);
 digitalWrite(3, LOW);
 digitalWrite(2, HIGH);
 delay(200);
 digitalWrite(2, LOW);
 digitalWrite(1, HIGH);
 delay(200);
 digitalWrite(1, LOW);
 digitalWrite(2, HIGH);
 delay(200);
 digitalWrite(2, LOW);
 digitalWrite(3, HIGH);
 delay(200);
 digitalWrite(3, LOW);
}
//jiga saklar tidak di tekan semua led mati
else (digitalRead(4)==LOW);
{digitalWrite(3, LOW);
 digitalWrite(2, LOW);
 digitalWrite(1, LOW);
}}