#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

const int SCREEN_WIDTH = 128; // OLED display width, in pixels
const int SCREEN_HEIGHT = 64; // OLED display height, in pixels

// Declaration for an SSD1306 display connected to I2C (SDA, SCL pins)
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

void setup() {
  Serial.begin(9600);
  pinMode(2, OUTPUT);
  pinMode(3, OUTPUT);
  pinMode(4, OUTPUT);
  pinMode(5, OUTPUT);
  pinMode(6, OUTPUT);
  pinMode(7, OUTPUT);

  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { // Address 0x3D for 128x64
    Serial.println(F("SSD1306 allocation failed"));
    while(true);
  }
}

void hijaukiri(){
  digitalWrite(4, HIGH);
  digitalWrite(3, LOW);
  digitalWrite(2, LOW);
  for(int i = 20; i >= 6; i--){
  display.clearDisplay();
  display.setTextSize(4);
  display.setTextColor(WHITE);
  display.setCursor(40,20);
  display.println(i);
  display.display();
  delay(1000);
  }
}
void kuningkiri(){
  digitalWrite(4, LOW);
  digitalWrite(3, HIGH);
  digitalWrite(2, LOW);
  for(int i = 5; i >= 1; i--){
  display.clearDisplay();
  display.setTextSize(4);
  display.setTextColor(WHITE);
  display.setCursor(40,20);
  display.println(i);
  display.display();
  delay(1000);
  }
}
void merahkiri(){
  digitalWrite(4, LOW);
  digitalWrite(3, LOW);
  digitalWrite(2, HIGH);
  for(int i = 40; i >= 6; i--){
  display.clearDisplay();
  display.setTextSize(4);
  display.setTextColor(WHITE);
  display.setCursor(40,20);
  display.println(i);
  display.display();
  delay(1000);
  }
}

void loop() {
hijaukiri();
kuningkiri();
merahkiri();
  }