Arduino joystick code

/*
Petry Arcade Stick --- Arduino section

Reads inputs from joystick microswitches and sends the data out over serial (115200 baud) as a int
 */

// constants won't change. They're used here to
// set pin numbers:
const int down = 6;
const int up = 7;
const int left = 4;
const int right = 5;
const int trigger = 3;

// variables will change:
int output = 0;

void setup() {
Serial.begin(115200);
pinMode(down, INPUT_PULLUP);
pinMode(right, INPUT_PULLUP);
pinMode(left, INPUT_PULLUP);
pinMode(up, INPUT_PULLUP);
pinMode(trigger, INPUT_PULLUP);
}

void loop() {
  if (digitalRead(up) == LOW) {
    output = 1 + output;
  }
  if (digitalRead(right) == LOW) {
    output = 7 + output;
  }
  if (digitalRead(down) == LOW) {
    output = 11 + output;
  }
  if (digitalRead(left) == LOW) {
    output = 15 + output;
  }
  if (digitalRead(trigger) == LOW) {
    output = 19 + output;
  }

  Serial.println(output);


  output = 0;
}