完成B树contains方法并且通过测试。

Author: shengshijun

src/main/java/ssj/algorithm/collections/BTree.java

@@ -68,11 +68,7 @@ private Tuple2<BTreeNode<T>, BTreeNode<T>> splitNode(BTreeNode<T> node, T insert
         right_node.setParent(parent_node);
         node.setParent(parent_node);
 
-//        System.out.println("parent : " + parent_node);
-//        System.out.println("insert ele : " + insert_ele);
-//        System.out.println("middle node : " + node.getValue(node.size() / 2));
         int mid_index = parent_node.appendValue(node.getValue(node.size() / 2));
-//        System.out.println("middle index : " + mid_index);
         parent_node.setChild(mid_index - 1, node);
         parent_node.setChild(mid_index + 1, right_node);
         node.splitNode(right_node);
@@ -108,6 +104,7 @@ public void delete(T ele) {
 
     }
 
+
     @Override
     public T successor(T value) {
         return null;
@@ -130,6 +127,13 @@ public T min() {
 
     @Override
     public boolean contains(T ele) {
+        for (BTreeNode<T> cur_node = root; cur_node != null; ) {
+            if (cur_node.contains(ele)) {
+                return true;
+            } else {
+                cur_node = cur_node.searchChild(ele);
+            }
+        }
         return false;
     }
 
@@ -324,5 +328,25 @@ public String toString() {
             sb.append("]");
             return sb.toString();
         }
+
+        public boolean contains(T value) {
+            Preconditions.checkNotNull(value);
+
+            for (int start = 1, end = size() - 2; start <= end; ) {
+                int mid = (start + end) / 2;
+                if (mid % 2 == 0) {
+                    mid--;
+                }
+                int com_res = getValue(mid).compareTo(value);
+                if (com_res == 0) {
+                    return true;
+                } else if (com_res > 0) {
+                    end = mid - 2;
+                } else {
+                    start = mid + 2;
+                }
+            }
+            return false;
+        }
     }
 }

src/test/java/ssj/algorithm/collections/BTreeTest.java

@@ -5,21 +5,24 @@
 
 import java.util.Arrays;
 
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
 /**
  * Created by shenshijun on 15/3/7.
  */
 public class BTreeTest {
     @Test
     public void testBasic() {
         BTree<Integer> tree = BTree.degreeOf(2);
-//        int[] data = new int[]{55, 34, 0, 21, 8, 47, 29, 26, 5, 60, 94, 58, 31, 24, 10, 79, 11, 57, 32, 36, 53, 2, 70, 6, 83, 49, 28, 96, 75, 35, 56, 77, 98, 80, 59, 85, 30, 4, 51, 72};
-//        int[] data = new int[]{55, 34, 0, 21, 8, 47, 29, 26,5, 60, 94,58};
         int[] data = MathUtil.randUniqueInt(0, 100000, 400);
-        System.out.println(Arrays.toString(data));
         for (int i : data) {
             tree.add(i);
         }
-        tree.size();
+        assertEquals(tree.size(), data.length);
+        for (int i : data) {
+            assertTrue(tree.contains(i));
+        }
     }
 
 }