Arduino battery guage

/*
 * *********************************************
 * *    Arduino 12V Battery Capacity Guage     *
 * *                                           *
 * *             learnelectronics              *
 * *         original code by R.Girish         *
 * *                                           *
 * *               Oct. 5, 2019                *
 * *                                           *
 * *     www.youtube.com/c/learnelectronics    *
 * *           arduino0169@gmail.com           *
 * *********************************************
 */


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

#define OLED_RESET 4
Adafruit_SSD1306 display(OLED_RESET);



int analogInput = 0;
int f=2;
int e=3;
int d=4;
int c=5;
int b=6;
int a=7;
int s=13;
float vout = 0.0;
float vin = 0.0;
float R1 = 100000;
float R2 = 10000;
int value = 0;


void setup()
{

display.begin(SSD1306_SWITCHCAPVCC, 0x3C);
display.display();
display.clearDisplay();

Serial.begin(9600);
pinMode(analogInput,INPUT);
pinMode(s,OUTPUT);
pinMode(a,OUTPUT);
pinMode(b,OUTPUT);
pinMode(c,OUTPUT);
pinMode(d,OUTPUT);
pinMode(e,OUTPUT);
pinMode(f,OUTPUT);
digitalWrite(s,LOW);
digitalWrite(a,HIGH);
delay(500);
digitalWrite(b,HIGH);
delay(500);
digitalWrite(c,HIGH);
delay(500);
digitalWrite(d,HIGH);
delay(500);
digitalWrite(e,HIGH);
delay(500);
digitalWrite(f,HIGH);
delay(500);
digitalWrite(a,LOW);
digitalWrite(b,LOW);
digitalWrite(c,LOW);
digitalWrite(d,LOW);
digitalWrite(e,LOW);
digitalWrite(f,LOW);
}
void loop()
{
value = analogRead(analogInput);
vout = (value * 5.0) / 1024;
vin = vout / (R2/(R1+R2));
  display.setTextSize(1);
  display.setTextColor(WHITE);
  display.setCursor(0,0);
  display.println("  Battery Voltage");
  display.println("");
  display.println("");
  display.setTextSize(3);
  display.print(" ");
  display.println(vin);
  display.display();
  delay(200);
  display.clearDisplay();



Serial.println("Input Voltage = ");
Serial.println(vin);
if(vin>12.46) {digitalWrite(a,HIGH);}
else { digitalWrite(a,LOW);}
if(vin<=12.46 && vin>12.28) {digitalWrite(b,HIGH);}
else { digitalWrite(b,LOW);}
if(vin<=12.28 && vin>12.12) {digitalWrite(c,HIGH);}
else { digitalWrite(c,LOW);}
if(vin<=12.12 && vin>11.98) {digitalWrite(d,HIGH);}
else { digitalWrite(d,LOW);}
if(vin<=11.98 && vin>11.90){digitalWrite(e,HIGH);}
else {digitalWrite(e,LOW);}
if(vin<=11.90) {digitalWrite(f,HIGH);}
else {digitalWrite(f,LOW);}
delay(2000);
}