So i was reading the official editorial of problem C: LCM, and i coudn't really understand why $$xy/gcd(x,y) = xy \sum\limits_{d|gcd(x,y)}{w_{d}}$$↵
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Also neither can i understand what does $w_{d}$ signify . Can someone please explain these or give resources to learn .↵
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[Problem Link](https://atcoder.jp/contests/agc038/tasks/agc038_c)↵
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[Editorial Link](https://img.atcoder.jp/agc038/editorial.pdf)
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Also neither can i understand what does $w_{d}$ signify . Can someone please explain these or give resources to learn .↵
↵
[Problem Link](https://atcoder.jp/contests/agc038/tasks/agc038_c)↵
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[Editorial Link](https://img.atcoder.jp/agc038/editorial.pdf)
