// https://forum.arduino.cc/t/my-code-for-is-not-working/1074619
//

#include<Servo.h> //include the servo library

int BUTTON1 = 5; //pin of the first button
int BUTTON2 = 4; //pin of the second button
int BUTTON3 = 3; //pin of the third button
int BUTTON4 = 2; //pin of the fourth button

int servoPin = 9; // Servo pin

Servo servo; //create a servo object

int pos = 0; //initial position of the servo

void setup() {
  // put your setup code here, to run once:
  //pin used by the servo
  servo.attach(9);
  pinMode(BUTTON1, INPUT_PULLUP); //define first button as input pullup
  pinMode(BUTTON2, INPUT_PULLUP); //define second button as input pullup
  pinMode(BUTTON3, INPUT_PULLUP); //define third button as input pullup
  pinMode(BUTTON4, INPUT_PULLUP); //define fourth button as input pullup
}

void loop() {
  if ((digitalRead(BUTTON2) == LOW) && (digitalRead(BUTTON3) == LOW)) { //if Value read of the button ==LOW:
    pos++; //increases the value of the "pos" variable each time the push button of the left is pressed
    // Keep the angle 'pos' from 0 to 180.
    pos = constrain(pos, 0, 180);
    delay(5); //5 milliseconds of delay
    servo.write(pos); //servo goes to variable pos
  }
  if ((digitalRead(BUTTON1) == LOW) && (digitalRead(BUTTON4) == LOW)) { //if Value read of the button ==LOW:
    pos--; //decreases the value of the "pos" variable each time the push button of the right is pressed
    // Keep the angle 'pos' from 0 to 180.
    pos = constrain(pos, 0, 180);
    delay(5); //5 milliseconds of delay
    servo.write(pos); //servo goes to variable pos
  }
}