Arduino - Interactive Traffic Lights with button

trafficlights.ino

int carRed = 12;     // assign the car lights
int carYellow = 11;
int carGreen = 10;
int pedRed = 8;     // assign the pedestrian lights
int pedGreen = 9;
int button = 2;     // button pin
int crossTime = 5000;     // time allowed to cross
unsigned long changeTime;     // time since button pressed
void setup() {
	pinMode(carRed, OUTPUT);
	pinMode(carYellow, OUTPUT);
	pinMode(carGreen, OUTPUT);
	pinMode(pedRed, OUTPUT);
	pinMode(pedGreen, OUTPUT);
	pinMode(button, INPUT); // button on pin 2
	// turn on the green light
	digitalWrite(carGreen, HIGH);
	digitalWrite(pedRed, HIGH);
}
void loop() {
	int state = digitalRead(button);
	/* check if button is pressed and it is
	   over 5 seconds since last button press */
	if (state == HIGH && (millis() - changeTime) > 5000) {
		// Call the function to change the lights
		changeLights();
	}
}
void changeLights() {
	digitalWrite(carGreen, LOW); // green off
	digitalWrite(carYellow, HIGH); // yellow on
	delay(2000); // wait 2 seconds
	digitalWrite(carYellow, LOW); // yellow off
	digitalWrite(carRed, HIGH); // red on
	delay(1000); // wait 1 second till its safe
	digitalWrite(pedRed, LOW); // ped red off
	digitalWrite(pedGreen, HIGH); // ped green on
	delay(crossTime); // wait for preset time period
	// flash the ped green
	for (int x=0; x<10; x++) {
		digitalWrite(pedGreen, HIGH);
		delay(250);
		digitalWrite(pedGreen, LOW);
		delay(250);
	}
	// turn ped red on
	digitalWrite(pedRed, HIGH);
	delay(500);
	digitalWrite(carYellow, HIGH); // yellow on
	digitalWrite(carRed, LOW); // red off
	delay(1000);
	digitalWrite(carGreen, HIGH);
	digitalWrite(carYellow, LOW); // yellow off
	// record the time since last change of lights
	changeTime = millis();
	// then return to the main program loop
}