#include <Wire.h> 
#include <Adafruit_GFX.h> 
#include <Adafruit_SSD1306.h> 
#define SCREEN_WIDTH 128 // OLED display width, in pixels 
#define SCREEN_HEIGHT 64 // OLED display height, in pixels 
// declare an SSD1306 display object connected to I2C 
Adafruit_SSD1306 oled(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1); 
void setup() {
  // put your setup code here, to run once:
Serial.begin(9600); // initialize OLED display with address 0x3C for 128x64 
if (!oled.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { 
Serial.println(F("SSD1306 allocation failed")); 
while (true); } delay(400); 
oled.setCursor(0,0); 
}

void loop() {
  // put your main code here, to run repeatedly:
oled.clearDisplay(); 
oled.drawRect(0, 15, 60, 40, WHITE); 
oled.display(); delay(2000); // fill rectangle 
oled.clearDisplay(); 
oled.fillRect(0, 15, 60, 40, WHITE); 
oled.display(); 
delay(2000); 
oled.clearDisplay(); 
oled.drawRoundRect(0, 15, 60, 40, 8, WHITE); 
oled.display(); delay(2000); // fill the round rectangle 
oled.clearDisplay(); 
oled.fillRoundRect(0, 15, 60, 40, 8, WHITE); 
oled.display(); 
delay(2000);
oled.clearDisplay(); 
oled.drawCircle(20, 35, 20, WHITE); 
oled.display(); delay(2000);  
oled.clearDisplay(); 
oled.fillCircle(20, 35, 20, WHITE); 
oled.display(); 
delay(2000); 
oled.clearDisplay(); 
oled.drawTriangle(30, 15, 0, 60, 60, 60, WHITE); 
oled.display(); delay(2000); // fill triangle 
oled.clearDisplay(); 
oled.fillTriangle(30, 15, 0, 60, 60, 60, WHITE); 
oled.display(); 
delay(2000);
}