Monitors.dib

#!markdown

# Common Resource - No Locks

#!csharp

const int NUMBER_OF_ITERATIONS = 32;
int globalSum = 0;

double result = 0d;
Task[] tasks = new Task[NUMBER_OF_ITERATIONS];

for (int i = 0; i < NUMBER_OF_ITERATIONS; i++)
{
    tasks[i] = Task.Run(() => 
    { 
        int cur = globalSum;
        Task.Delay(NUMBER_OF_ITERATIONS - i /2 + 1);
        globalSum = cur + 1;  
    });
}

Task.WaitAll(tasks);
Console.WriteLine(globalSum);

#!markdown

# Common Resource - With Locks

#!csharp

const int NUMBER_OF_ITERATIONS = 32;
int globalSum = 0;
object forGlobalLock = new object();

double result = 0d;
Task[] tasks = new Task[NUMBER_OF_ITERATIONS];

for (int i = 0; i < NUMBER_OF_ITERATIONS; i++)
{
    tasks[i] = Task.Run(() => 
    { 
        lock (forGlobalLock)
        {
            int cur = globalSum;
            Task.Delay(NUMBER_OF_ITERATIONS - i /2 + 1);
            globalSum = cur + 1; 
        }
    });
}

Task.WaitAll(tasks);
Console.WriteLine(globalSum);