// set pin numbers
const int buttonPin = 7; // the number of the pushbutton pin
const int redLed = 13;
const int yellowLed = 12;
const int greenLed = 11; // the number of the LED pin
// variable for storing the pushbutton status
int buttonState = 0;

void setup() {
Serial.begin(9600);
// initialize the pushbutton pin as an input
pinMode(buttonPin, INPUT);
// initialize the LED pin as an output
pinMode(redLed, OUTPUT);
pinMode(yellowLed, OUTPUT);
pinMode(greenLed, OUTPUT);

}

void loop() 
{
// read the state of the pushbutton value
buttonState = digitalRead(buttonPin);
Serial.println(buttonState);
// check if the pushbutton is pressed.
// if it is, the buttonState is HIGH
if (buttonState == HIGH) 
{
// turn LED on
digitalWrite(redLed, HIGH);
delay(1000);
digitalWrite(redLed, LOW);

digitalWrite(yellowLed, HIGH);
delay(1500);
digitalWrite(yellowLed, LOW);

digitalWrite(greenLed, HIGH);
delay(2000);
digitalWrite(greenLed, LOW);

} else 
{
digitalWrite(redLed, HIGH);
delay(340);
digitalWrite(redLed, LOW);

digitalWrite(yellowLed, HIGH);
delay(340);
digitalWrite(yellowLed, LOW);

digitalWrite(greenLed, HIGH);
delay(340);
digitalWrite(greenLed, LOW);

}
}