/*#define G1 2
#define Y1 4
#define R1 5
#define G2 19
#define Y2 18
#define R2 21



void setup() {
  // initialize digital pin LED_BUILTIN as an output.
  pinMode(G1, OUTPUT);//Green1
  pinMode(Y1, OUTPUT);//Yellow1
  pinMode(R1, OUTPUT);//Red1
  pinMode(Y2, OUTPUT);//Yellow2
  pinMode(G2, OUTPUT);//Green2
  pinMode(R2, OUTPUT);//Red2
  }
*/


// the setup function runs once when you press reset or power the board
void setup() {
  // initialize digital pin LED_BUILTIN as an output.
  pinMode(2, OUTPUT);//Green1
  pinMode(4, OUTPUT);//Yellow1
  pinMode(5, OUTPUT);//Red1
  pinMode(18, OUTPUT);//Yellow2
  pinMode(19, OUTPUT);//Green2
  pinMode(21, OUTPUT);//Red2
  }

// the loop function runs over and over again forever
void loop() {

  /*Case:1 (Red1 & Green2) are on)*/
  digitalWrite(2, LOW);   // turn the LED on (HIGH is the voltage level) yellow1                    
  digitalWrite(4, LOW);   // turn the LED on (HIGH is the voltage level)  Green1
  digitalWrite(5, HIGH);    // turn the LED off by making the voltage LOW Red1
  
  digitalWrite(18, LOW);    // turn the LED off by making the voltage LOW  yellow2
  digitalWrite(19, HIGH);    // turn the LED off by making the voltage LOW Green2
  digitalWrite(21, LOW);   // turn the LED on (HIGH is the voltage level) Red2
  delay(5000);// Pin 17 Other Traffic 
 
  /*Case:2 (Red1 & Yellow2) are on)*/
  digitalWrite(2, LOW);    // turn the LED off by making the voltage LOW Yellow1
  digitalWrite(4, LOW);    // turn the LED off by making the voltage LOW Green1
  digitalWrite(5, HIGH);   // turn the LED on (HIGH is the voltage level)  Red1
  
  digitalWrite(18, HIGH);    // turn the LED off by making the voltage LOW Yellow2
  digitalWrite(19, LOW);    // turn the LED off by making the voltage LOW  Green2
  digitalWrite(21, LOW);   // turn the LED on (HIGH is the voltage level) Red2
  delay(2000);// Pin 16 Other Traffic  

   /*Case:3 (Green2 & Red2) are on)*/      
  digitalWrite(2, LOW);    // turn the LED off by making the voltage LOW Yellow1
  digitalWrite(4, HIGH);    // turn the LED off by making the voltage LOW   Green1
  digitalWrite(5, LOW);    // turn the LED off by making the voltage LOW   Red1
  
  digitalWrite(18, LOW);    // turn the LED off by making the voltage LOW  Yellow2
  digitalWrite(19, LOW);    // turn the LED off by making the voltage LOW  Green2
  digitalWrite(21, HIGH);   // turn the LED on (HIGH is the voltage level) Red2
  delay(5000);// Pin 5 Other Traffic  


  /*Case:4 (Yellow1 & Red2) are on)*/
  digitalWrite(2, HIGH);    // turn the LED off by making the voltage LOW Yellow1
  digitalWrite(4, LOW);    // turn the LED off by making the voltage LOW   Green1
  digitalWrite(5, LOW);    // turn the LED off by making the voltage LOW   Red1
  
  digitalWrite(18, LOW);    // turn the LED off by making the voltage LOW  Yellow2
  digitalWrite(19, LOW);    // turn the LED off by making the voltage LOW  Green2
  digitalWrite(21, HIGH);   // turn the LED on (HIGH is the voltage level) Red2
  delay(2000);// Pin 5 Other Traffic  
     
  
 
  
  

  
    
}