/*
  Arduino | coding-help
  AmBored — 7:00 PM
  Hey im trying to program a calculator and display it on my lcd
  but the code isnt calculating properly and i cant debug the problem.
  Do you guys know what i missed?
*/

#include <LiquidCrystal.h>

const int rs = 12;
const int e = 11;
const int D4 = 10;
const int D5 = 9;
const int D6 = 8;
const int D7 = 7;

LiquidCrystal lcd(rs, e, D4, D5, D6, D7);

String Operator ;
float firstnumber  ;
float secondnumber ;
float result ;

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600) ;
  lcd.begin(16, 2);
}

void loop() {
  // put your main code here, to run repeatedly:
  lcd.setCursor(0, 0);
  lcd.print("Enter your 1st");
  lcd.setCursor(0, 1);
  lcd.print("number: ");
  Serial.println("Enter your first number") ;
  while (Serial.available() == 0) {

  }

  firstnumber = Serial.parseFloat() ;
  lcd.print(firstnumber);
  delay(1000);
  lcd.clear() ;
  lcd.setCursor(0, 0);
  lcd.print("Enter your 2nd");
  lcd.setCursor(0, 1);
  lcd.print("number");
  Serial.println("Enter your second number") ;
  while (Serial.available() == 0) {

  }

  secondnumber = Serial.parseFloat() ;
  lcd.clear() ;
  lcd.setCursor(0, 0);
  lcd.print("Pick an operator");
  lcd.setCursor (0, 1) ;
  lcd.print("- + * / ") ;
  Serial.println("Pick an operator") ;

  while (Serial.available() == 0) {

  }

  Operator = Serial.readString() ;

  if (Operator == "-") {
    result = firstnumber - secondnumber ;
  }

  if (Operator == "+") {
    result = firstnumber + secondnumber ;
  }

  if (Operator == "*") {
    result = firstnumber * secondnumber ;
  }

  if (Operator == "/") {
    result = firstnumber / secondnumber ;
  }

  lcd.clear() ;
  lcd.setCursor(0, 0) ;
  lcd.print("Your answer is") ;
  lcd.setCursor(0, 1) ;
  lcd.print(result) ;
  delay(1000) ;
  Serial.print("Your answer is ") ;
  Serial.println(result, 4);
  lcd.clear() ;
}