/**
   HC-SR04 Distance Sensor Example
   https://wokwi.com/arduino/projects/304444938977804866
*/

#define PIN_TRIG 3
#define PIN_ECHO 2

void setup() {
  Serial.begin(115200);
  pinMode(PIN_TRIG, OUTPUT);
  pinMode(PIN_ECHO, INPUT);
 
}

void loop() {
   double raio = 4;
  double volmax = 500;
  double h=0;
  double volume = 0;
  // Start a new measurement:
  digitalWrite(PIN_TRIG, HIGH);
  delayMicroseconds(10);
  digitalWrite(PIN_TRIG, LOW);

  // Read the result:
  int duration = pulseIn(PIN_ECHO, HIGH);

 
  h = duration / 58;
 Serial.println(h);
  volume = 3.1416*raio*raio*(403-h);
 Serial.print("Volume: ");
Serial.println(volume);
  delay(1000);
}