GPT-4 and AlphaCode are two code-generation tools that were evaluated on Codeforces programming contests. GPT-4 achieved a rating of 392 points, which is considered low compared to human participants, but surprisingly better than other mentioned exams and contests. AlphaCode, on the other hand, achieved a top-level Pupil rating with an estimated pass rate of over 45% on newly generated tests. This was made possible by its architecture, which includes both code generation and integrity agents that work together to generate high-quality solutions. The code integrity agent is particularly crucial in filtering out non-working solutions, making AlphaCode's performance stand out from other LLMs like GPT-4 and Bard.