Added check that counting array isn't empty; avoids crash when file does not exist

Sorting/CountingSorter.java

@@ -7,6 +7,7 @@ public class CountingSorter extends Sorter{
     }
 
     void sort(){
+        if(numbers.length!=0){
             int min = numbers[0];
             int max = numbers[0];
             for(int e: numbers){
@@ -30,5 +31,6 @@ public class CountingSorter extends Sorter{
                 }
             }
         }
+    }
     
 }