int pinbtn = 7;
int pinled = 6;
int ptnvlu;
int oldvlu;

String ledstate = "off";


void setup() {
  // put your setup code here, to run once:
  pinMode(pinbtn,  INPUT_PULLUP );
  pinMode(pinled, OUTPUT);
  Serial.begin(9600);
  oldvlu = 1;
}

void loop() {
  // put your main code here, to run repeatedly:
  ptnvlu = digitalRead(pinbtn);

  if (ptnvlu == 0) 
  {
    if (oldvlu == 1)
    {
      if (ledstate == "off") 
      {
        digitalWrite(pinled, HIGH);
        ledstate = "on";
      }
      else 
      {
        digitalWrite(pinled, LOW);
        ledstate = "off";
      }
    }
  }
  
  oldvlu = ptnvlu;
  delay(100);
  Serial.println(ledstate);
  Serial.println(ptnvlu);
  Serial.println(oldvlu);
  // if (ptnvlu == 0) {
  //   digitalWrite(pinled, HIGH);
  // }
  // else {
  //   digitalWrite(pinled, LOW);
  // }
  // Serial.println(ptnvlu);

}