Why does the serial monitor not work

Projects Programming
1

Hello. I want some help with the serial monitor.

const int motorpin1 = 22;
const int motorpin2 = 23;
const int motorpin3 = 24;
const int motorpin4 = 25;
const int trigPin1 = 8;
const int echoPin1 = 9;
long duration;
int distance;
bool detected;
void Forward() {
  digitalWrite(motorpin1, LOW);
  digitalWrite(motorpin2, HIGH);
  digitalWrite(motorpin3, HIGH);
  digitalWrite(motorpin4, LOW);
}
void Stop() {

  digitalWrite(motorpin1, LOW);
  digitalWrite(motorpin2, LOW);
  digitalWrite(motorpin3, LOW);
  digitalWrite(motorpin4, LOW);
}


void measure() {
  digitalWrite(10, HIGH);
  digitalWrite(trigPin1, LOW);
  delayMicroseconds(5);
  digitalWrite(trigPin1, HIGH);
  delayMicroseconds(15);
  digitalWrite(trigPin1, LOW);
  pinMode(echoPin1, INPUT);
  duration = pulseIn(echoPin1, HIGH);
  distance = (duration * 0.034) / 2; //obtain distance
}

void setup() {
  // put your setup code here, to run once:
  pinMode (22, OUTPUT);
  pinMode (23, OUTPUT);
  pinMode (24, OUTPUT);
  pinMode (25, OUTPUT);
  pinMode(trigPin1, OUTPUT);
  pinMode(echoPin1, INPUT);


}

void loop() {
  // put your main code here, to run repeatedly:
  Serial.print (distance);
}

Now, when I upload this code, the serial monitor does not give any response.
Please help and thanks in advance.

2

Serial.begin?

3

try adding Serial.begin(9600); to your void setup()