From cbef5275bb5ac2b34d4ec0ed986cb1129486e85a Mon Sep 17 00:00:00 2001
From: shubhamguptaji <shubham2604gupta@gmail.com>
Date: Thu, 11 Oct 2018 09:50:16 +0530
Subject: [PATCH 1/2] Trie Tree

---
 Datastructures/TrieTree.cpp | 93 +++++++++++++++++++++++++++++++++++++
 1 file changed, 93 insertions(+)
 create mode 100644 Datastructures/TrieTree.cpp

diff --git a/Datastructures/TrieTree.cpp b/Datastructures/TrieTree.cpp
new file mode 100644
index 000000000..abf0da08b
--- /dev/null
+++ b/Datastructures/TrieTree.cpp
@@ -0,0 +1,93 @@
+#include<iostream>
+#include<string.h>
+#include<stdbool.h>
+using namespace std;
+
+typedef struct trie
+{
+    struct trie *arr[26];
+    bool isEndofWord;
+} trie;
+
+trie *createNode()
+{
+    trie *nn = new trie();
+    for (int i = 0; i < 26; i++)
+        nn->arr[i] = NULL;
+    nn->isEndofWord = false;
+    return nn;
+}
+
+void insert(trie *root, char* str)
+{
+    for (int i = 0; i < strlen(str); i++)
+    {
+        int j = str[i] - 'a';
+        if (root->arr[j])
+        {
+            root = root->arr[j];
+        }
+        else
+        {
+            root->arr[j] = createNode();
+            root = root->arr[j];
+        }
+    }
+    root->isEndofWord = true;
+}
+
+bool search(trie *root, char* str, int index)
+{
+    if (index == strlen(str))
+    {
+        if (!root->isEndofWord)
+            return false;
+        return true;
+    }
+    int j = str[index] - 'a';
+    if (!root->arr[j])
+        return false;
+    return search(root->arr[j], str, index + 1);
+}
+
+bool deleteString (trie *root, char* str, int index)
+{
+    if (index == strlen(str))
+    {
+        if (!root->isEndofWord)
+            return false;
+        root->isEndofWord = false;
+        for (int i = 0; i < 26; i++)
+            return false;
+        return true;
+    }
+    int j = str[index] - 'a';
+    if (!root->arr[j])
+        return false;
+    bool var = deleteString (root, str, index + 1);
+    if (var)
+    {
+        root->arr[j] = NULL;
+        if (root->isEndofWord)
+            return false;
+        else
+        {
+            int i;
+            for (i = 0; i < 26; i++)
+                if (root->arr[i])
+                    return false;
+            return true;
+        }
+    }
+}
+
+int main()
+{
+    trie *root = createNode();
+    insert(root, "hello");
+    insert(root, "world");
+    int a = search(root, "hello", 0);
+    int b = search(root, "word", 0);
+    printf("%d %d ", a, b);
+    return 0;
+}
\ No newline at end of file

From 975cefb62b25d492f45ec217c116649a24b5515f Mon Sep 17 00:00:00 2001
From: shubhamguptaji <shubham2604gupta@gmail.com>
Date: Thu, 11 Oct 2018 09:57:49 +0530
Subject: [PATCH 2/2] comments added

---
 Datastructures/TrieTree.cpp | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/Datastructures/TrieTree.cpp b/Datastructures/TrieTree.cpp
index abf0da08b..866087d87 100644
--- a/Datastructures/TrieTree.cpp
+++ b/Datastructures/TrieTree.cpp
@@ -2,13 +2,13 @@
 #include<string.h>
 #include<stdbool.h>
 using namespace std;
-
+// structure definition
 typedef struct trie
 {
     struct trie *arr[26];
     bool isEndofWord;
 } trie;
-
+// create a new node for trie 
 trie *createNode()
 {
     trie *nn = new trie();
@@ -18,6 +18,7 @@ trie *createNode()
     return nn;
 }
 
+// insert string into the trie 
 void insert(trie *root, char* str)
 {
     for (int i = 0; i < strlen(str); i++)
@@ -36,6 +37,7 @@ void insert(trie *root, char* str)
     root->isEndofWord = true;
 }
 
+// search a string exists inside the trie
 bool search(trie *root, char* str, int index)
 {
     if (index == strlen(str))
@@ -49,7 +51,9 @@ bool search(trie *root, char* str, int index)
         return false;
     return search(root->arr[j], str, index + 1);
 }
-
+/* removes the string if it is not a prefix of any  other 
+ string, if it is then just sets the endofword to false, else 
+ removes the given string*/
 bool deleteString (trie *root, char* str, int index)
 {
     if (index == strlen(str))