#define LED 5
#define btn 4
void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  pinMode(LED,OUTPUT);
  pinMode(btn,INPUT);

}
void Blink_LED(){
  for(int i=0;i<5;i++){
    digitalWrite(LED,HIGH);
    delay(500);
    digitalWrite(LED,LOW);
    delay(500);
  }
}

void loop() {
  bool ReadSwitch = digitalRead(btn);
  if(ReadSwitch==LOW){
    Serial.println("Pressed switch");
    Blink_LED();
  }
  
}