Challenge: Up walker

Make a walker tend up instead of right, using probability.

Make it a blob

Hint

if (r < ) { this.x++; } else if (r < ) { this.x--; } else if (r < ) { this.y++; } else { this.y--; }

Currently, our walker tends to walk to the right. Change the logic so that it has a 10% chance of walking right, 10% chance of walking left, 60% chance of walking up, and 20% chance of walking down.