const int LED1 = 26;
const int LED2 = 27;
const int LED3 = 13;
const int BUTTON1 = 18;
const int BUTTON2 = 19;
int buttonState = 0;
int lastbuttonState = 0; 

void setup()
{
pinMode(LED1, OUTPUT);
pinMode(LED2, OUTPUT);
pinMode(LED3, OUTPUT);
pinMode(BUTTON1, INPUT);
pinMode(BUTTON2, INPUT);
}

void loop()
{
buttonState = digitalRead(BUTTON1);
lastbuttonState = digitalRead(BUTTON2);

if(buttonState == LOW && lastbuttonState == HIGH)
{
  digitalWrite(LED1, HIGH);
  digitalWrite(LED2, LOW);
  digitalWrite(LED3, LOW);
}
else if(buttonState == HIGH && lastbuttonState == LOW)
{
  digitalWrite(LED1, HIGH);
  digitalWrite(LED2, HIGH);
  digitalWrite(LED3, LOW);
}
else if (buttonState == LOW && lastbuttonState == LOW)
{
  digitalWrite(LED1, LOW);
  digitalWrite(LED2, LOW);
  digitalWrite(LED3, HIGH);
}
else {
  digitalWrite(LED1, LOW);
  digitalWrite(LED2, LOW);
  digitalWrite(LED3, LOW);
}

}