#define led1 16
#define led2 17
#define btn 18

void setup() {
  Serial.begin(115200);
  pinMode(led1, OUTPUT);
  pinMode(led2, OUTPUT);
  pinMode(btn, INPUT);
  Serial.println("Hello, ESP32!");
}

void loop() {
  int button = digitalRead(btn);
  if(button==1){
    Serial.println("on");
    digitalWrite(led1, LOW);
    digitalWrite(led2, HIGH);
    delay(1000);
    digitalWrite(led1, HIGH);
    digitalWrite(led2, LOW);
    delay(1000);
  }
  if(button==0){
    Serial.println("off");
    digitalWrite(led1, LOW);
    digitalWrite(led2, LOW);
    delay(1000);
    digitalWrite(led1, HIGH);
    digitalWrite(led2, HIGH);
    delay(1000);
  }
  
}