206 Concealed Square.sf 424 B

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  1. #!/usr/bin/ruby
  2. # Author: Trizen
  3. # Date: 24 August 2016
  4. # Translated: 16 November 2023
  5. # https://github.com/trizen
  6. # https://projecteuler.net/problem=206
  7. # Runtime: 0.263s
  8. var n = isqrt(1020304050607080900) # lower-limit
  9. var m = isqrt(1929394959697989990) # upper-limit
  10. for (var i = (m + (10 - (m % 10))) ; i >= n ; i -= 10) {
  11. if (i.sqr.to_s =~ /^1.2.3.4.5.6.7.8.9.0\z/) {
  12. say i
  13. break
  14. }
  15. }