A particle is set to travel in a random path inside a 2-dimensional domain of size 100 100 grid points. The particle is released at the position (1, 1) and its movement is tracked until it reaches the endpoint. It can freely move inside the domain, but it is not allowed to cross the border. Its movement is determined by taking a random step in - and - directions. Let (,) be the current position of the particle and the new position of the particle, (, ) can be described as follows, (,) = ( + , + ) where and are randomly sampled from a domain [20, 20]. If is positive, then the particle will move to the right by steps and if is negative, then the particle will move to the left. A similar scenario applies to , but in upward and downward directions. For example, let the initial position of the particle is at (5, 12), and = 8 and = 5, then the new position of the particle is at (13, 7). It means the particle has moved 8 steps to the right and 5 steps downward. Note that the particle is not allowed to cross the border, hence and must always satisfy the following conditions, a) , 1 b) , 100 If the particle touches the border, then it will be bounced back into the domain at the remaining steps. For instance, let the particle is at (10, 4), and = 7 and = 15. The particles new position should be at (17, 11). However, since < 1, hence the particle will bounce back 11 steps upward, making its new position is at (17, 11). The particle will stop moving when both and are greater than 90.