finished the generate possibilites function for ETP

src/main/java/edu/rpi/legup/puzzle/binary/rules/EliminateTheImpossibleDirectRule.java

@@ -25,42 +25,62 @@ public EliminateTheImpossibleDirectRule() {
     }
 
     // Function to generate all binary strings
-    void generateAllBinaryStrings(double countTo, int spots, ArrayList<String> possibilities)
+    void generatePossibilitites(int spots, ArrayList<String> possibilities, int zeroCount, int oneCount)
     // This function generates all the possible combinations of 0s and 1s for a certain size, it does this
     // by basically just counting from 0 to the number - 1, so if you want all the possible combinations for 3
     // spots, you can just count in binary from 0 to 7 (taking 3 spots, so from 000 to 111). To be practical,
     // the function does not return an array with all the possibilities as an array, but populates the 
     // arraylist you pass in (possibilities)
     {
-        int count = (int)countTo;
+       if(zeroCount + oneCount != spots){
+            System.out.println("INVALID INPUT");
+            return;
+        }
+
+        if(zeroCount == spots){
+            String zero = "";
+            for(int i = 0; i < spots; i++){
+                zero = zero + "0";
+            }
+            possibilities.add(zero);
+
+        }
+        int count = (int)Math.pow(2,spots) -1;
         int finalLen = spots;
-
         Queue<String> q = new LinkedList<String>();
         q.add("1");
+
         while (count-- > 0) {
             String s1 = q.peek();
             q.remove();
-            
+
             String newS1 = s1;
             int curLen = newS1.length();
-
             int runFor = spots - curLen;
             if(curLen < finalLen){
-
-
                 for(int i = 0; i < runFor; i++){
                     newS1 = "0" + newS1;
                 }
-
             }
-
-            System.out.println(newS1);
-            possibilities.add(newS1);
+            int curZeros = 0;
+            int curOnes = 0;
+
+            for(int i = 0; i < spots; i++){
+                if(newS1.charAt(i) == '0'){
+                    curZeros++;
+                }
+                if(newS1.charAt(i) == '1'){
+                    curOnes++;
+                }
+            }
+
+            if(zeroCount == curZeros && oneCount == curOnes){
+                possibilities.add(newS1);
+            }
             String s2 = s1;
             q.add(s1 + "0");
             q.add(s2 + "1");
-        }
-
+        } 
     }
 
     @Override
@@ -74,8 +94,12 @@ public String checkRuleRawAt(TreeTransition transition, PuzzleElement puzzleElem
         BinaryCell binaryCell = (BinaryCell) puzzleElement;
 
         ArrayList<String> result = new ArrayList<String>();
-        generateAllBinaryStrings(16,4,result);
 
+        int zerosLeft = 3;
+        int onesLeft = 1;
+        generatePossibilitites(4, result, zerosLeft, onesLeft);
+
+        System.out.println("printing result");
         for(String s : result){
             System.out.println(s);
         }