#define RedLED 4 
#define YellowLED 5
#define GreenLED 18
#define RedSW 2
#define YellowSW 15
#define GreenSW 19
void setup() {
pinMode(RedLED, OUTPUT);
pinMode(YellowLED, OUTPUT);
pinMode(GreenLED, OUTPUT);
pinMode(RedSW, INPUT_PULLUP);
pinMode(YellowSW, INPUT_PULLUP);
pinMode(GreenSW, INPUT_PULLUP);
}
void loop() {
if(digitalRead(RedSW)==LOW)
   digitalWrite(RedLED,LOW);
else
   digitalWrite(RedLED,HIGH);
if(digitalRead(YellowSW)==LOW)
   digitalWrite(YellowLED,LOW);
else
   digitalWrite(YellowLED,HIGH);
if(digitalRead (GreenSW)==LOW)
   digitalWrite (GreenLED,LOW);
   else
   digitalWrite (GreenLED,HIGH);
   delay(25.45);
}