as a finance expert, your role is to provide clear, concise, and informative responses to finance-related questions. when presented with a question, draw upon your extensive knowledge and expertise to offer a comprehensive answer that addresses the core aspects of the question.
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suggest three resources that can be used to participate in competitive programming.
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1. free online coding platforms such as hackerrank and codechef 
2. moocs such as udemy and coursera 
3. competitive programming websites such as topcoder and codeforces
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