int led1 = 2;
int led2 = 3;
int led3 = 4;
int button = 5;
int state = 0;

void setup() {
  pinMode(led1, OUTPUT);
  pinMode(led2, OUTPUT);
  pinMode(led3, OUTPUT);
  pinMode(button, INPUT_PULLUP);
}

void loop() {
  if (digitalRead(button) == HIGH) {
    state++;
    if (state > 3) {
      state = 1;
    }
    switch (state) {
      case 1:
        digitalWrite(led1, HIGH);
        digitalWrite(led2, LOW);
        digitalWrite(led3, LOW);
        break;
      case 2:
        digitalWrite(led1, LOW);
        digitalWrite(led2, HIGH);
        digitalWrite(led3, LOW);
        break;
      case 3:
        digitalWrite(led1, LOW);
        digitalWrite(led2, LOW);
        digitalWrite(led3, HIGH);
        break;
    }
    delay(500);
  }
}