void setup() 
{
 pinMode(13, OUTPUT);
 pinMode(12, OUTPUT);
 pinMode(8, OUTPUT);
 pinMode(7, OUTPUT);
 pinMode(3, INPUT);
 pinMode(4, INPUT);
 pinMode(5, INPUT);
 attachInterrupt(digitalPinToInterrupt(2), letup, RISING);
}

void loop()
{
 int button1= digitalRead(3);
 int button2= digitalRead(4);
 int button3= digitalRead(5);
 

 if(button1==HIGH)
 {
 digitalWrite(13, HIGH);
 digitalWrite(12, LOW); 
 digitalWrite(7, HIGH);
 digitalWrite(8, LOW);
 }

 if(button2==HIGH)
 {
  digitalWrite(13, LOW);
  digitalWrite(12, HIGH);
  digitalWrite(7, LOW);
  digitalWrite(8, HIGH);
 }

 if(button3==HIGH)
 {
  digitalWrite(13, LOW);
  digitalWrite(12, LOW);
  digitalWrite(7, LOW);
  digitalWrite(8, LOW);
 }
}

 void letup()
 {
  digitalWrite(13, LOW);
  digitalWrite(12, LOW);
  digitalWrite(7, LOW);
  digitalWrite(8, LOW);
 
}