Question 39
Today, on September 23, 2023, twins Mari and Jüri received a total of $5000$ candies for their $10$th birthdays. Starting from this day, their mother allows them both to take candies once per day, such that the amount of candies taken by any child on any day is less than their age in full years (on their birthday, they already use their new age). Neither child can resist taking at least one candy every day. Jüri allows Mari to take candies first on every day. The children agreed that whoever takes the last candy, has to buy new candies. Which child can ensure that they do not have to buy new candies, no matter how the other child takes their candies?