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thanh phan
232 PointsWhy we need add * -1?
Can anyone explain it? I don't understand why we need add * -1.
Update: https://teamtreehouse.com/library/serializing-to-a-file sr guys, my question for this video.
David Tomko
7,744 PointsI actually just learned this at work the other day. Basically the compareTo returns a 1 if the thing being compared is less than what it's compared to. It returns a 0 if they're equal, and a -1 if the thing being compared is more than what it's compared to. So multiplying by -1 will order the results in descending order. Where normally it is in ascending order.
David Tomko
7,744 PointsI actually just learned this at work the other day. Basically the compareTo returns a 1 if the thing being compared is less than what it's compared to. It returns a 0 if they're equal, and a -1 if the thing being compared is more than what it's compared to. So multiplying by -1 will order the results in descending order. Where normally it is in ascending order.
Steven Parker
231,122 PointsDavid Tomko — Did you realize you just added the same comment as you put here last month?
Steven Parker
231,122 PointsSteven Parker
231,122 PointsI'm not sure what you're asking about. If it's something from a video, could you provide a link to the video and an approximate time index? And if it's a quiz or challenge, could you provide a link to that page and show the complete code you're working with?