Found a problem in the comparator of the Interval Tree

git-svn-id: https://java-algorithms-implementation.googlecode.com/svn/trunk@434 032fbc0f-8cab-eb90-e552-f08422b9a96a

Author: phishman3579

src/com/jwetherell/algorithms/data_structures/IntervalTree.java

@@ -28,10 +28,17 @@ public class IntervalTree<O extends Object> {
          */
         @Override
         public int compare(IntervalData<?> arg0, IntervalData<?> arg1) {
+        	// Compare start first
             if (arg0.start < arg1.start)
                 return -1;
             if (arg1.start < arg0.start)
                 return 1;
+            //  Then end
+            if (arg0.end < arg1.end)
+                return -1;
+            if (arg1.end < arg0.end)
+                return 1;
+            // if they have the same start and end they must be equal
             return 0;
         }
     };
@@ -43,10 +50,17 @@ public int compare(IntervalData<?> arg0, IntervalData<?> arg1) {
          */
         @Override
         public int compare(IntervalData<?> arg0, IntervalData<?> arg1) {
+        	// Compare end first
             if (arg0.end < arg1.end)
                 return -1;
             if (arg1.end < arg0.end)
                 return 1;
+            //  Then start
+            if (arg0.start < arg1.start)
+                return -1;
+            if (arg1.start < arg0.start)
+                return 1;
+            // if they have the same start and end they must be equal
             return 0;
         }
     };
@@ -68,10 +82,12 @@ protected static final <O extends Object> Interval<O> createFromList(List<Interv
         Interval<O> newInterval = new Interval<O>();
         int half = intervals.size() / 2;
         IntervalData<O> middle = intervals.get(half);
+        System.out.println(middle);
         newInterval.center = ((middle.start + middle.end) / 2);
         List<IntervalData<O>> leftIntervals = new ArrayList<IntervalData<O>>();
         List<IntervalData<O>> rightIntervals = new ArrayList<IntervalData<O>>();
         for (IntervalData<O> interval : intervals) {
+        	System.out.println(interval);
             if (interval.end < newInterval.center) {
                 leftIntervals.add(interval);
             } else if (interval.start > newInterval.center) {