Fix getReachableStates() method (#3)

Toflar · Oct 5, 2023 · 0c8e1e0 · 0c8e1e0
1 parent 394b25d
commit 0c8e1e0
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Showing 2 changed files with 10 additions and 7 deletions.
diff --git a/src/StateSetIndex.php b/src/StateSetIndex.php
@@ -181,12 +181,15 @@ private function getReachableStates(int $startState, int $editDistance, int $cur
         // A state is always able to reach itself
         $reachable->add($startState, $currentDistance);
 
-        for ($i = 0; $i <= $editDistance; $i++) {
-            for ($c = 0; $c < $this->config->getAlphabetSize(); $c++) {
-                $state = $startState + $c * $i;
-                if ($this->stateSet->has($state)) {
-                    $reachable->add($startState, $currentDistance);
-                }
+        if ($currentDistance === $editDistance) {
+            return $reachable;
+        }
+
+        for ($c = 1; $c <= $this->config->getAlphabetSize(); $c++) {
+            $state = $startState * $this->config->getAlphabetSize() + $c;
+            if ($this->stateSet->has($state)) {
+                $reachable->add($state, $currentDistance + 1);
+                $reachable = $reachable->mergeWith($this->getReachableStates($state, $editDistance, $currentDistance + 1));
             }
         }
 

diff --git a/tests/StateSetIndexTest.php b/tests/StateSetIndexTest.php
@@ -58,4 +58,4 @@ public function testAssassinCanBeFound(): void
 
         $this->assertSame(['assassin'], $stateSetIndex->find('assasin', 2));
     }
-}
+}