False triggering on my Arduino Nano

Projects General Guidance
38 
// C++ code
//
int buttonState = 0;

void setup() {
  pinMode(5, OUTPUT);
  pinMode(10, INPUT_PULLUP);
  pinMode(7, OUTPUT);
  pinMode(9, OUTPUT);
  pinMode(11, INPUT_PULLUP);
  pinMode(2, OUTPUT);
  pinMode(12, INPUT_PULLUP);
  pinMode(6, OUTPUT);
  pinMode(3, OUTPUT);
  pinMode(13, INPUT_PULLUP);
  pinMode(4, OUTPUT);

  digitalWrite(5, HIGH);
  pinMode(5, OUTPUT);
  // BLOCKS LS. 3
}