php version of 2 - simple rewrite...

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" );
+}
+