This question already has an answer here:
After raising a flag, as initially user couldn't understand the language, and found any answer not worthy. But after that he came to know about the worth of answer and, edit it by emphasizing the line (that he skipped) and upvote the answer as answer was really helpful.
But user can't take his flag back. Ah! No scope for correcting the mistake. Or I am the only one who is not aware of it? Here is the Example.