int led1=19, led2=18, led3=5, led4=17;
int sw1=2, sw2=15;

void setup() {
  pinMode(led1,OUTPUT);
  pinMode(led2,OUTPUT);
  pinMode(led3,OUTPUT);
  pinMode(led4,OUTPUT);
  pinMode(sw1,INPUT);
  pinMode(sw2,INPUT);
}

void loop() {
  if(digitalRead(sw1)==HIGH)  step1();
  else if(digitalRead(sw2)==HIGH)  step2();
  else{
    digitalWrite(led1,LOW);
    digitalWrite(led2,LOW);
    digitalWrite(led3,LOW);
    digitalWrite(led4,LOW);
  }
}

void step1(){
  digitalWrite(led1,1);
  digitalWrite(led2,0);
  digitalWrite(led3,0);
  digitalWrite(led4,0);
  delay(1000);
  digitalWrite(led1,0);
  digitalWrite(led2,1);
  digitalWrite(led3,0);
  digitalWrite(led4,0);
  delay(1000);
  digitalWrite(led1,0);
  digitalWrite(led2,0);
  digitalWrite(led3,1);
  digitalWrite(led4,0);
  delay(1000);
  digitalWrite(led1,0);
  digitalWrite(led2,0);
  digitalWrite(led3,0);
  digitalWrite(led4,1);
  delay(1000);
  digitalWrite(led1,0);
  digitalWrite(led2,0);
  digitalWrite(led3,0);
  digitalWrite(led4,0);
  delay(1000);
}

void step2(){
  digitalWrite(led1,0);
  digitalWrite(led2,0);
  digitalWrite(led3,0);
  digitalWrite(led4,1);
  delay(1000);
  digitalWrite(led1,0);
  digitalWrite(led2,0);
  digitalWrite(led3,1);
  digitalWrite(led4,0);
  delay(1000);
  digitalWrite(led1,0);
  digitalWrite(led2,1);
  digitalWrite(led3,0);
  digitalWrite(led4,0);
  delay(1000);
  digitalWrite(led1,1);
  digitalWrite(led2,0);
  digitalWrite(led3,0);
  digitalWrite(led4,0);
  delay(1000);
  digitalWrite(led1,0);
  digitalWrite(led2,0);
  digitalWrite(led3,0);
  digitalWrite(led4,0);
  delay(1000);
}