Circuit diagram

Code

#define SENSE A0

void setup()

{

pinmode(SENSE, INPUT);

pinMode(13, OUTPUT);

pinMode(LED_BUILTIN, OUTPUT);

}

void loop ()

{

if(digitalRead(SENSE))

{

digitalWrite(LED_BUILTIN, LOW);

pinMode(13, LOW);

}

else

{

delay(3000);

if(digitalRead(SENSE))

{

digitalWrite(LED_BUILTIN, LOW);

pinMode(13, LOW);

}

else

digitalWrite(LED_BUILTIN, HIGH);

pinMode(13, HIGH);

}

}

                        Total Cost