Mango-man's blog

By Mango-man, history, 4 years ago, In English

how to solve this problem ?1265B - Beautiful Numbers

here is my submission in python 82612211

ok sorry for the joke if you don't find it funny.

but seriously i am not able to understand the idea of the editorial. please help me in this problem.

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4 years ago, # |
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This is how I solved this problem: I was iterating from 1 to n. Let l is the leftmost position of all number from 1 to i, and r — the rightmost one. Then i is a good number if and only if (r — l + 1) == i. Do you need a proof of that?