#define buttonpin 10
#define ledpin 12
void setup() {
pinMode(buttonpin, INPUT);
pinMode(ledpin, OUTPUT);
digitalWrite(ledpin, HIGH);
}

void loop() {
  if(digitalRead(buttonpin) == 0)
  {
    while(digitalRead(buttonpin) == 0);
    delay(300);
  if(digitalRead(ledpin) == 1)
  {
    digitalWrite(ledpin, LOW);
  }else
  {
    digitalWrite(ledpin, HIGH);
  }
} 
}