byte LED = 18;
byte sw = 25;
byte VP=36;


void setup() {
  pinMode(sw, INPUT);
  pinMode(LED, OUTPUT);
  Serial.begin(9600);
}
bool vstate = LOW;
unsigned long pre_time = 0;
unsigned long delay_time = 5000;

void loop() {
  unsigned long cur_time = millis();
  if(cur_time -pre_time > delay_time){
    vstate = !vstate;
    digitalWrite(LED,vstate);
    pre_time = cur_time;
  }
  int vsw;
  vsw = digitalRead(sw);
  Serial.println(vsw);

}