diff options
| -rw-r--r-- | challenge-133/ben-davies/raku/ch-1.raku | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/challenge-133/ben-davies/raku/ch-1.raku b/challenge-133/ben-davies/raku/ch-1.raku index 98fd70d0ee..44ce0d2ba2 100644 --- a/challenge-133/ben-davies/raku/ch-1.raku +++ b/challenge-133/ben-davies/raku/ch-1.raku @@ -1,4 +1,12 @@ use v6; unit sub MAIN(Int:D $n where * > 0) { - say (1..$n).first({ $^x == $n div $^x }); + # Newton's method. Adapted from Algorithm 1.13 of: + # https://maths-people.anu.edu.au/~brent/pd/mca-cup-0.5.9.pdf + my $x; + my $L = $n; + repeat { + $x = $L; + $L = ($x + $n div $x) div 2; + } until $L >= $x; + say $x; } |