const int redLED=13;
const int greenLED=12;
const int yellowLED=7;
void setup(){
pinMode(redLED,OUTPUT);
pinMode(yellowLED,OUTPUT);
pinMode(greenLED,OUTPUT);
Serial.begin(9600);
}
void loop(){
  //red light or led
  digitalWrite(redLED, HIGH);

  digitalWrite(greenLED, LOW);

  digitalWrite(yellowLED, LOW);
    Serial.println("vechile will stop now");
  delay(1000);

  
//yellow led
  digitalWrite(redLED, LOW);
 
  digitalWrite(greenLED, LOW);
  
  digitalWrite(yellowLED, HIGH);
   Serial.println("vechile will ready now");

  delay(1000);
 
  
//green led
     digitalWrite(redLED, LOW);
     
    
  
    digitalWrite(yellowLED, LOW);
   
    digitalWrite(greenLED, HIGH);
    Serial.println("vechile will go now");
    delay(1000);
    
  

}