when I had the code run just the LCD it worked perfectly fine. but when I added an HC-SR04 without changing the text it showed weird characters. All I had the code to do with the hc-SR04 was print it in the serial monitor.

#include <LiquidCrystal.h>

// initialize the library by associating any needed LCD interface pin
// with the arduino pin number it is connected to
const int rs = 5, e = 4, d4 = 3, d5 = 2, d6 = 1, d7 = 0;
const int trigPin = A0;
const int echoPin = A1;
LiquidCrystal lcd(rs, e, d4, d5, d6, d7);

void setup() {
  // set up the LCD's number of columns and rows:
  Serial.begin(9600);
    lcd.begin(16, 2);
      lcd.print("zach is cool");
   pinMode(trigPin,OUTPUT);
  pinMode(echoPin,INPUT);
}

void loop() {
  // set the cursor to column 0, line 1
  // (note: line 1 is the second row, since counting begins with 0):
    long duration, inches, cm;
      lcd.setCursor(0, 1);
   digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

duration = pulseIn(echoPin, HIGH);

  inches = microsecondsToInches(duration);
  cm = microsecondsToCentimeters(duration);

Serial.print(inches);
  Serial.print("in, ");
  Serial.print(cm);
  Serial.print("cm");
  Serial.println();

  delay(100);
}
long microsecondsToInches(long microseconds) {
  // According to Parallax's datasheet for the PING))), there are 73.746
  // microseconds per inch (i.e. sound travels at 1130 feet per second).
  // This gives the distance travelled by the ping, outbound and return,
  // so we divide by 2 to get the distance of the obstacle.
  // See: https://www.parallax.com/package/ping-ultrasonic-distance-sensor-downloads/
  return microseconds / 74 / 2;
}

long microsecondsToCentimeters(long microseconds) {
  // The speed of sound is 340 m/s or 29 microseconds per centimeter.
  // The ping travels out and back, so to find the distance of the object we
  // take half of the distance traveled.
  return microseconds / 29 / 2;
}

When I had the code run just the LCD it worked perfectly fine, but when I added an HC-SR04 without changing the text it showed weird characters. All I had the code do with the HC-SR04 was print it in the serial monitor.

// include the library code:
#include <LiquidCrystal.h>

// initialize the library by associating any needed LCD interface pin
// with the arduino pin number it is connected to
const int rs = 5, e = 4, d4 = 3, d5 = 2, d6 = 1, d7 = 0;
const int trigPin = A0;
const int echoPin = A1;
LiquidCrystal lcd(rs, e, d4, d5, d6, d7);

void setup() {
  // set up the LCD's number of columns and rows:
  Serial.begin(9600);
  lcd.begin(16, 2);
  lcd.print("zach is cool");
  pinMode(trigPin,OUTPUT);
  pinMode(echoPin,INPUT);
}

void loop() {
  // set the cursor to column 0, line 1
  // (note: line 1 is the second row, since counting begins with 0):
  long duration, inches, cm;
  lcd.setCursor(0, 1);
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

  duration = pulseIn(echoPin, HIGH);

  inches = microsecondsToInches(duration);
  cm = microsecondsToCentimeters(duration);

  Serial.print(inches);
  Serial.print("in, ");
  Serial.print(cm);
  Serial.print("cm");
  Serial.println();

  delay(100);
}

long microsecondsToInches(long microseconds) {
  // According to Parallax's datasheet for the PING))), there are 73.746
  // microseconds per inch (i.e. sound travels at 1130 feet per second).
  // This gives the distance travelled by the ping, outbound and return,
  // so we divide by 2 to get the distance of the obstacle.
  // See: https://www.parallax.com/package/ping-ultrasonic-distance-sensor-downloads/
  return microseconds / 74 / 2;
}

long microsecondsToCentimeters(long microseconds) {
  // The speed of sound is 340 m/s or 29 microseconds per centimeter.
  // The ping travels out and back, so to find the distance of the object we
  // take half of the distance traveled.
  return microseconds / 29 / 2;
}