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I'm a second year computer science student in Australia. I hope to apply to one of the top 10 US universities for MS or PhD program. I have received high distinction (highest grade possible here) for all my courses since my first year of university, have done an internship at a major company, and have published one paper. However, I received a 'fail' for a course I took at my current university while I was a senior in high school, which shows on my university transcript. Will this greatly affect my chances at graduate school?