feat: RandUtil nextBool false 엔트로피 절약

src/sammo/RandUtil.php

@@ -42,9 +42,12 @@ class RandUtil
         if ($prob >= 1) {
             return true;
         }
-        if($prob === 0.5){
+        if ($prob === 0.5){
             return $this->nextBit();
         }
+        if ($prob <= 0){
+            return false;
+        }
         return $this->nextFloat1() < $prob;
     }