int led=10;
int buttonpin=7;
int val=0;
void setup() {
  // put your setup code here, to run once:
  //decided output-led decide input-pushbutton
  //switch button press value become 1 store in val function
  //at that time led to be high by and vice vesra by using if else statemen
{
  pinMode(led, OUTPUT);
  pinMode(buttonpin, INPUT);
}
}

void loop() {
  // put your main code here, to run repeatedly
  val==digitalRead(buttonpin);
  if(val==LOW)//if button press val is 0 ie low led blink
  {
    digitalWrite(led,HIGH);
  }
  else
  {
  digitalWrite(led, LOW);
}
}