int led = 3; int sensor = 4; // the setup routine runs once when you press reset: void setup() { // initialize the digital pin as an output. pinMode(led, OUTPUT); pinMode(sensor, INPUT); } // the loop routine runs over and over again forever: void loop() { digitalWrite(led, LOW); if (digitalRead(sensor)) { digitalWrite(led, HIGH); delay(30000); if (digitalRead(sensor)) { digitalWrite(led, HIGH); delay(15000); } delay(10000); } else digitalWrite(led, LOW); }