Fixed Bug when make comparative check DT#5496

main/survey/survey.lib.php

@@ -4017,6 +4017,7 @@ class SurveyUtil {
 		}
 
 		$counter = 0;
+		if(is_array($answers_x)){
 			foreach ($answers_x as $user => $answers)
 			{
 				// check if the user has given $option_x as answer
@@ -4029,6 +4030,7 @@ class SurveyUtil {
 					}
 				}
 			}
+		}
 		return $counter;
 	}
 	/**