#define BUTTON_PIN 32
#define RELAY_PIN 18

int relay_state = LOW;
int button_state;
int last_button_states;

void setup() {
  Serial.begin(115200);
  Serial.println("Hello, ESP32!");
  pinMode(BUTTON_PIN, INPUT_PULLUP);
  pinMode(RELAY_PIN, OUTPUT);
}

void loop() {
  button_state = digitalRead(BUTTON_PIN);

  if (last_button_states == HIGH && button_state == LOW) {
    Serial.println("The button is presed (Bouncing occur)");
    relay_state = !relay_state;
    digitalWrite(RELAY_PIN, relay_state);
  }
  last_button_states = button_state;
}