diff options
Diffstat (limited to 'challenge-102/james-smith/php/ch-2.php')
| -rw-r--r-- | challenge-102/james-smith/php/ch-2.php | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/challenge-102/james-smith/php/ch-2.php b/challenge-102/james-smith/php/ch-2.php new file mode 100644 index 0000000000..015733e992 --- /dev/null +++ b/challenge-102/james-smith/php/ch-2.php @@ -0,0 +1,22 @@ +<?php + +foreach( range(1,20) as $_ ) { + echo hash_count_string($_),"\n"; +} + +## Like many of these problems - we can work backwards... +## We know the string is going to be just the # +## or the end of the string is going to be nnnn# (where nnnn is the strlen of the string) +## we can repeat this backwards until we reach the start of the string. +## note for the start of the string there are two posibilities +## If you get to "2#" at the start then you have finished +## If you have a single gap just prefix by "#" + +function hash_count_string($n) { + $s = ''; + do { + if( $n == strlen($s) ) return $s; + if( $n-1 == strlen($s) ) return "#$s"; + } while( $s = ($n-strlen($s)) ."#$s" ); +} + |