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Here are some problems that we hope will appeal to curious and inquisitive students. Take a look, we think you'll get hooked on them!
Here are some problems that require you to be resilient. We hope you'll stick with them and feel a sense of achievement at the end!
Here are some problems that require careful consideration. Immerse yourself in them - we think they are worth the effort!
Here are some problems that are ideal for working on with others. Find a friend, share ideas, and see if two heads really are better than one!