int sw = 2;
int sw2 = 3;
int sw3 = 4;
int sw4 = 5;
int led = 13;
int led2 = 12;
int led3 = 11;
int led4 = 10;
int led_status = 0;
void setup() {
  pinMode(sw, INPUT_PULLUP);
  pinMode(sw2, INPUT_PULLUP);
  pinMode(sw3, INPUT_PULLUP);
  pinMode(sw4, INPUT_PULLUP);
  pinMode(led, OUTPUT);
  pinMode(led2, OUTPUT);
  pinMode(led3, OUTPUT);
  pinMode(led4, OUTPUT);
}
void off_led2()
{  digitalWrite(led, LOW);
  digitalWrite(led3, LOW);
  digitalWrite(led4, LOW);
}
void off_led3()
{  digitalWrite(led, LOW);
  digitalWrite(led2, LOW);
  digitalWrite(led4, LOW);
}
void off_led4()
{  digitalWrite(led, LOW);
  digitalWrite(led2, LOW);
  digitalWrite(led3, LOW);
}
void off_led1()
{  digitalWrite(led2, LOW);
  digitalWrite(led3, LOW);
  digitalWrite(led4, LOW);
}

void loop() {
  if(digitalRead(sw)==0){
    if(led_status==0){
      digitalWrite(led,1);
      led_status =1;
    }else{
      digitalWrite(led,0);
      led_status = 0;
    }
    delay(250);
  }
  if(digitalRead(sw2)==0){
    if(led_status==0){
      digitalWrite(led2,1);
      led_status =1;
    }else{
      digitalWrite(led2,0);
      led_status = 0;
    }
    delay(250);
  }
  if(digitalRead(sw3)==0){
    if(led_status==0){
      digitalWrite(led3,1);
      led_status =1;
    }else{
      digitalWrite(led3,0);
      led_status = 0;
    }
    delay(250);
  }
  if(digitalRead(sw4)==0){
    if(led_status==0){
      digitalWrite(led4,1);
      led_status =1;
    }else{
      digitalWrite(led4,0);
      led_status = 0;
    }
    delay(250);
  }
}