int red = 4;
int blue = 3;
int green = 2;
int btn = 1;

bool red_color = true;
bool blue_color = false;
bool green_color = false;
bool btn_pressed = false;

void setup()
{
  pinMode( btn, INPUT );
  pinMode( red, OUTPUT );
  pinMode( blue, OUTPUT );
  pinMode( green, OUTPUT );
  
  digitalWrite( red, HIGH );
  digitalWrite( blue, LOW );
  digitalWrite( green, LOW );
}

void loop()
{
  if( digitalRead( btn ) == LOW )
  {
	  btn_pressed = false;
  }
  else if( ( digitalRead( btn ) == HIGH ) && !btn_pressed )
  {
    btn_pressed = true;
    
    if( red_color )
    {
      digitalWrite( red, LOW );
      digitalWrite( blue, HIGH );
      digitalWrite( green, LOW );
      red_color = false;
      blue_color = true;
    }
    else if( blue_color )
    {
      digitalWrite( red, LOW );
      digitalWrite( blue, LOW );
      digitalWrite( green, HIGH );
      blue_color = false;
      green_color = true;
    }
    else
    {
      digitalWrite( red, HIGH );
      digitalWrite( blue, LOW );
      digitalWrite( green, LOW );
      green_color = false;
      red_color = true;
    }
  }
  
  delay(100);
}