Keypad + WaterFlow Sensor

int ledPin = 13;
int TurnOffVolume = 600;

//--------------------------  YF-S201 Sensor  ------------------------------------------
//---------------------------------------------./Global Variables-----------------------
int sensorPin = 2;
float k = 6.0337;
volatile long NumPulses;
float volume = 0;

void CountPulses() {
  NumPulses++;
}

void Volume(int number_of_pulses) {
  volume = (number_of_pulses * 1.00) / (k * 60.00 / 1000.0); // Volume in milli-Liters
}
//--------------------------------------------------------------------------------------


void setup() {

  Serial.begin(9600);
  pinMode(ledPin, OUTPUT);
  //--------------------------  YF-S201 Sensor  ----------------------------------------
  //-----------------------------------------------./Setup------------------------------
  pinMode(sensorPin, INPUT);
  attachInterrupt(0, CountPulses, RISING);
  interrupts();
  //------------------------------------------------------------------------------------
}

void loop() {

  if (volume + 60 >= TurnOffVolume) {
    digitalWrite(ledPin, HIGH);
  }
  else {
    digitalWrite(ledPin, LOW);
  }
  //--------------------------  YF-S201 Sensor  ----------------------------------------
  //-----------------------------------------------./Loop-------------------------------
  Volume(NumPulses);
  /*
    Serial.print("Number of Pulses: :");
    Serial.println(NumPulses);
    Serial.print("\n\nVolume of Liquid: :");
    Serial.print(volume / 1000.0);
    Serial.println(" Liter");
    Serial.print("Volume of Liquid: :");
    Serial.print(volume);
    Serial.println(" mL");
    Serial.println("--------------------------------");*/
  delay(100);
  //------------------------------------------------------------------------------------
}



#include <Keypad.h>
long value = 0;
const byte ROWS = 4; //four rows
const byte COLS = 4; //four columns
char keys[ROWS][COLS] = {
  {'1', '4', '7', '*'},
  {'2', '5', '8', '0'},
  {'3', '6', '9', '#'},
  {'A', 'B', 'C', 'D'}
};
byte rowPins[ROWS] = {7, 6, 5, 4}; //connect to the row pinouts of the keypad
byte colPins[COLS] = {11, 10, 9, 8}; //connect to the column pinouts of the keypad
Keypad keypad = Keypad( makeKeymap(keys), rowPins, colPins, ROWS, COLS );
void setup() {
  Serial.begin(9600);
}
void loop() {

  char key = keypad.getKey();
  if (key == 'A' || key == 'B' || key == 'C' || key == 'D') {
    Serial.print("");
  }
  else Serial.print(key);
  delay(1);
  if (key != NO_KEY)
  {
    if ( (key >= '0') && (key <= '9') )
    {
      value = value * 10;
      value = value + key - '0';
    }
    if ( key == 'A' )
    {
      Serial.println();
      Serial.println(value);
      // Remove this line and add it to the sensor value checker complete
      value = 0; //Now reset ready for next input
    }
  }
  if (key == 'B')
  {
    value = 0; //Now reset ready for next input
    Serial.println();
    Serial.println("Enter A New Number Please:");
  }
  if (key == 'C')
  {
    // Do whatever you like
    //digitalWrite(ValvePin, LOW); // if relay is Active LOW
  }
  if (key == 'D')
  {
    // Do whatever you like
    //digitalWrite(ValvePin, HIGH); // if relay is Active LOW
  }

}//end of loop