-Cap1taL-'s blog

By -Cap1taL-, history, 5 months ago, In English

https://mirror.codeforces.com/contest/1175/submission/238928196 For judging whether an array of length n is a 1~n permutation, I judged its sum{i^1} sum{i^2} sum{i^3} sum{i^4} and passed. Can anyone hack this solution or prove it correct? please help me :(

Full text and comments »

  • Vote: I like it
  • +1
  • Vote: I do not like it