Create main.cpp

Author: JawadSher

18 - Binary Search Tree Data Structure Problems/05 - Check for BST/main.cpp

@@ -0,0 +1,20 @@
+class Solution {
+  public:
+    bool isBST(Node* root, Node* & prev){
+        if(root == NULL) return true;
+        
+        if(!isBST(root -> left, prev)) return false;
+        
+        if(prev != NULL && root -> data <= prev -> data) return false;
+        
+        prev = root;
+        
+        return isBST(root -> right, prev);
+        
+    }
+    
+    bool isBST(Node* root) {
+        Node* prev = NULL;
+        return isBST(root, prev);
+    }
+};