int red1=8;
int green1=6;
int yellow1=7;
int red2=3;
int green2=5;
int yellow2=4;
const int pingPin = 10; // Trigger Pin of Ultrasonic Sensor
const int echoPin = 9; // Echo Pin of Ultrasonic Sensor
const int pingPin2 = 12; // Trigger Pin of Ultrasonic Sensor
const int echoPin2 = 11; // Echo Pin of Ultrasonic Sensor

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  pinMode(red1,OUTPUT);
  pinMode(red2,OUTPUT);
  pinMode(yellow1,OUTPUT);
  pinMode(yellow2,OUTPUT);
  pinMode(green1,OUTPUT); 
  pinMode(green2,OUTPUT);
}
void loop() {
  // put your main code here, to run repeatedly:
  int distance1,distance2;
  distance1=calculatedistance(pingPin , echoPin);
  Serial.print("Distance1= ");
  Serial.println(distance1);
  distance2=calculatedistance(pingPin2 , echoPin2);
  Serial.print("Distance2= ");
  Serial.println(distance2);
  if(distance1>=distance2){
     digitalWrite(red1,LOW);
     digitalWrite(green2,LOW);
     digitalWrite(red2,LOW);
     digitalWrite(green1,LOW);
     digitalWrite(yellow1,HIGH);
     digitalWrite(yellow2,HIGH);
     delay(200);
     while(distance1>distance2){
       distance1=calculatedistance(pingPin , echoPin);
       distance2=calculatedistance(pingPin2 , echoPin2);
       digitalWrite(red1,HIGH);
       digitalWrite(green2,HIGH);
       digitalWrite(red2,LOW);
       digitalWrite(green1,LOW);
       digitalWrite(yellow1,LOW);
       digitalWrite(yellow2,LOW);
       Serial.print("Distance1= ");
       Serial.println(distance1);
       Serial.print("Distance2= ");
       Serial.println(distance2);
       Serial.println("Higher traffic of vehicles on Lane 2");
       delay(2000);
      }
    }
    if(distance2>=distance1){
      digitalWrite(red1,LOW);
      digitalWrite(green2,LOW);
      digitalWrite(red2,LOW);
      digitalWrite(green1,LOW);
      digitalWrite(yellow1,HIGH);
      digitalWrite(yellow2,HIGH);
      delay(200);
      while(distance2>distance1){
        distance1=calculatedistance(pingPin , echoPin);
        distance2=calculatedistance(pingPin2 , echoPin2);
        digitalWrite(red1,LOW);
        digitalWrite(green2,LOW);
        digitalWrite(red2,HIGH);
        digitalWrite(green1,HIGH);
        digitalWrite(yellow1,LOW);
        digitalWrite(yellow2,LOW);
        Serial.print("Distance1= ");
       Serial.println(distance1);
       Serial.print("Distance2= ");
       Serial.println(distance2);
       Serial.println("Higher traffic of vehicles on Lane 1");
       delay(2000);
      }
    }
  }
  long microsecondsToCentimeters(long microseconds)
  {
   return microseconds / 29 / 2;
  }
  int calculatedistance(int pingPin , int echoPin){
    long duration, inches, cm,meter;
    pinMode(pingPin, OUTPUT);
    digitalWrite(pingPin, LOW);
    delayMicroseconds(2);
    digitalWrite(pingPin, HIGH);
    delayMicroseconds(10);
    digitalWrite(pingPin, LOW);
    pinMode(echoPin, INPUT);
    duration = pulseIn(echoPin, HIGH);
    cm = microsecondsToCentimeters(duration);
    return cm;
  }