A race condition occurs when two or more threads can access shared data and they try to change it concurrently. Because the kernel can swap between threads at any time, you don't know the order in which the threads will attempt to access the shared data.

In the following, we will create a program that stores a global variable, global, initialized to 0.We also create two pThreads that attempt to access the shared variable. thread1 is a thread that increments global 90,000,000 times, while thread2 concurrently decrements global the same number of times.

1. What is the expected value of global when both threads have finished executing?