Visual Proximity Detector for Arduino UNO

A visual proximity detector specifically to work with Arduino UNO boards. This code is for use with a HC-SR04 ultrasonic sensor and 3 LED lights to display proximity. Components I used to make a circuit for this are:

1 Arduino UNO

3 LED lights

3 120 Ohm resistors. 220 Ohm would work nicely as well.

1 HC-SR04 Ultrasonic sensor

9 wires

1 small sized Breadboard

Here is a diagram of the finished circuit!