commit kthMinimumElement.cpp

Trees/kthMinimumElement.cpp

@@ -0,0 +1,60 @@
+// from a given BST, the program will find out the kth smallest element (hardcoded)
+
+#include <bits/stdc++.h>
+using namespace std;
+
+struct node
+{
+ int key;
+ struct node *left, *right;
+};
+
+struct node *newNode(int item)
+{
+ struct node *temp = (struct node *)malloc(sizeof(struct node));
+ temp->key = item;
+ temp->left = temp->right = NULL;
+ return temp;
+}
+struct node *insert(struct node *node, int key)
+{
+ if (node == NULL)
+ return newNode(key);
+
+ if (key < node->key)
+ node->left = insert(node->left, key);
+ else if (key > node->key)
+ node->right = insert(node->right, key);
+
+ return node;
+}
+void saveNode(struct node *root, vector<struct node *> &nodes)
+{
+ if (root == NULL)
+ return;
+
+ saveNode(root->left, nodes);
+ nodes.push_back(root);
+ saveNode(root->right, nodes);
+}
+
+int findKthMin(struct node *root, int k)
+{
+ vector<struct node *> nodes;
+ saveNode(root, nodes);
+
+ return nodes[k - 1]->key;
+}
+
+int main()
+{
+ int k = 1;
+ struct node *root = NULL;
+ root = insert(root, 5);
+ insert(root, 2);
+ insert(root, 1);
+ insert(root, 9);
+ insert(root, 5);
+ insert(root, 8);
+ cout << "The " << k << "st smallest element in Binary search tree is " << findKthMin(root, k);
+}