#define data_pin 7
#define latch_pin 8
#define clock_pin 9
#define PIN_TRIG 12
#define PIN_ECHO 11
long duration, cm;
int digits [10] = {252,96,218,242,102,182,190,224,254,246};
void setup() {
    pinMode(data_pin, OUTPUT);
    pinMode(latch_pin, OUTPUT);
    pinMode(clock_pin, OUTPUT);
    digitalWrite(latch_pin, LOW);
    Serial.begin (9600);
    pinMode(PIN_TRIG, OUTPUT);
    pinMode(PIN_ECHO, INPUT);
    pinMode(10, INPUT_PULLUP);
}

void loop() {
  if (digitalRead(10) == 0) {  
    shiftOut(data_pin,clock_pin, LSBFIRST, digits[cm % 10]); // 3
    shiftOut(data_pin,clock_pin, LSBFIRST, digits[int(cm / 10 % 10)]); // 2
    shiftOut(data_pin,clock_pin, LSBFIRST, digits[int(cm / 100)]+1); // 1
    digitalWrite(latch_pin, HIGH);
    digitalWrite(latch_pin, LOW);
    digitalWrite(PIN_TRIG, LOW);
    delayMicroseconds(5);
    digitalWrite(PIN_TRIG, HIGH);
    delayMicroseconds(10);
    digitalWrite(PIN_TRIG, LOW);
    duration = pulseIn(PIN_ECHO, HIGH);
    cm = (duration / 2) / 29.1;
    Serial.print("Расстояние до объекта: ");
    Serial.print(cm);
    Serial.println(" см.");
    delay(1000);
  }
}