Implementing Queue Data Structure in C

# Introduction

In this challenge, we will implement the functionality of a queue data structure in C. We have provided the basic code for the queue, but the four methods `front()`, `pop()`, `count()`, and `is_empty()` need to be completed. You will need to modify the code according to the comments provided in the code. The goal is to ensure that the program behaves as expected and performs the required operations on the queue. You will need to use system libraries and make sure that the path and filename of `/home/labex/project/queue.c` do not change for correct evaluation.