#include <SoftI2CMaster.h>
#include <LiquidCrystal_SoftI2C.h>

LiquidCrystal_SoftI2C mylcd(0x27,16,2,9,8);

float checkdistance_4_3() {
  digitalWrite(4, LOW);
  delayMicroseconds(2);
  digitalWrite(4, HIGH);
  delayMicroseconds(10);
  digitalWrite(4, LOW);
  float distance = pulseIn(3, HIGH) / 58.00;
  delay(10);
  return distance;
}

void setup(){
  mylcd.init();
  mylcd.backlight();
  pinMode(4, OUTPUT);
  pinMode(3, INPUT);
}

void loop(){
  mylcd.setCursor(0, 0);
  mylcd.print(String(checkdistance_4_3()) + String("  cm"));
  mylcd.setCursor(0, 1);
  mylcd.print("");
  mylcd.clear();
  delay(100);

}