#include <SPI.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
const int s1=2,s2=3,s3=4,s4=5;
// Canvas size
const int a = 128;
const int b = 64;
const int reset = -1;
int info,old_info=0;
byte u=10,v=15;
// Create display
Adafruit_SSD1306 display(a, b, &Wire, reset);

void setup() {
  Serial.begin(115200);
  for(int b=2;b<=5;b++){
    pinMode(b, INPUT_PULLUP);
  }
  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println("SSD1306 allocation failed");
    for (;;)
      ;  // Don't proceed, loop forever
  }
  display.display();
  delay(500);
  display.clearDisplay();
  delay(200);
}
void display_text(String text, int x, int y) {
  display.setTextSize(1);       // Normal 1:1 pixel scale
  display.setTextColor(WHITE);  // Draw white text
  display.setCursor(x, y);      // Start at top-left corner                       
  display.println(text);
  display.display();
}
void draw_fill(int xx,int yy,int widt,int heit){
  display.fillRect(xx,yy,widt,heit,WHITE);
}
void loop() {
  //display.clearDisplay();
  if(digitalRead(s1)==LOW){display.clearDisplay();v++;}
  else if(digitalRead(s4)==LOW){display.clearDisplay();v--;}
  else if(digitalRead(s3)==LOW){display.clearDisplay();u--;}
  else if(digitalRead(s2)==LOW){display.clearDisplay();u++;}
   if(u>128){u=128;}
   if(v>64){v=64;}
  display_text("press button to move rect",0,0);
  display.drawRect(30,40,40,15,WHITE);
  draw_fill(u,v,35,13);
}