chore(CPlusCPlus): add trie algorithms (#1006)

algorithms/CPlusPlus/README.md

@@ -157,6 +157,8 @@
 ## Trie
 
 - [Trie for searching](Trie/trie_search.cpp)
+- [Trie for insert search and prefix_search](Trie/trie_insert_search_startWith.cpp)
+- [Trie for delete](Trie/trie_delete.cpp)
 
 # Maths
 

algorithms/CPlusPlus/Trie/trie_delete.cpp

@@ -0,0 +1,44 @@
+#include<bits/stdc++.h>
+using namespace std;
+typedef long long ll;
+#define inf 1e9;
+#define inf2 2e18;
+
+
+
+struct custom_hash {
+   static uint64_t splitmix64(uint64_t x) { x += 0x9e3779b97f4a7c15; x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9; x = (x ^ (x >> 27)) * 0x94d049bb133111eb; return x ^ (x >> 31);}
+   size_t operator()(uint64_t x) const { static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count(); return splitmix64(x + FIXED_RANDOM); }
+};
+
+
+
+struct TrieNode{ TrieNode* child[26]; bool isEnd;
+    TrieNode(){ isEnd = false; for(int i = 0; i<26; i++){ child[i] = NULL; } }
+};
+struct TrieNode* rootTrie;
+void addTrie(string& s){ TrieNode* curr = rootTrie; for(int i = 0; i<s.length(); i++){ int n = s[i] - 'a';if(curr->child[n] == NULL){curr->child[n] = new TrieNode();} curr = curr->child[n]; } curr->isEnd = true; }
+bool searchTrie(string& s){TrieNode* curr = rootTrie;for(int i = 0; i<s.length(); i++){int n = s[i] - 'a';if(!curr->child[n]) return false;curr = curr->child[n];}return curr->isEnd;}
+bool startsWithTrie(string s) {int n = s.length();TrieNode* curr = rootTrie;for(int i  =0 ; i<n; i++){int k = s[i] - 'a';if(curr->child[k] == NULL) return false;curr = curr->child[k];}return true;}
+bool isEmpty(TrieNode* rootTrie){ for (int i = 0; i < ALPHABET_SIZE; i++){if(rootTrie->child[i])return false;}return true;}
+void remove(TrieNode* rootTrie, string key, int depth = 0){if (!rootTrie)return NULL;if (depth == key.size()) {if (rootTrie->isEnd)rootTrie->isEnd = false;if (isEmpty(rootTrie)) {delete (rootTrie);rootTrie = NULL;}return rootTrie;}int index = key[depth] - 'a';rootTrie->child[index] = remove(rootTrie->child[index], key, depth + 1);if (isEmpty(rootTrie) && rootTrie->isEnd == false) {delete (rootTrie);rootTrie = NULL;}return rootTrie;}
+
+
+int main(){
+//Jai Shree Ram
+    ios_base::sync_with_stdio(false);
+    cin.tie(NULL);
+    
+    string keys[] = { "the", "a", "there", "answer", "any", "by", "bye", "their", "hero", "heroplane" };
+    int n = sizeof(keys) / sizeof(keys[0]);
+ 
+    for (int i = 0; i < n; i++)
+        insert(rootTrie, keys[i]);
+ 
+    search(rootTrie, "the") ? cout << "Yes\n" : cout << "No\n";
+    search(rootTrie, "these") ? cout << "Yes\n" : cout << "No\n";
+ 
+    remove(rootTrie, "heroplane");
+    search(rootTrie, "hero") ? cout << "Yes\n" : cout << "No\n";
+    return 0;
+}

algorithms/CPlusPlus/Trie/trie_insert_search_startWith.cpp

@@ -0,0 +1,44 @@
+#include<bits/stdc++.h>
+using namespace std;
+typedef long long ll;
+#define inf 1e9;
+#define inf2 2e18;
+
+
+
+struct custom_hash {
+   static uint64_t splitmix64(uint64_t x) { x += 0x9e3779b97f4a7c15; x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9; x = (x ^ (x >> 27)) * 0x94d049bb133111eb; return x ^ (x >> 31);}
+   size_t operator()(uint64_t x) const { static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count(); return splitmix64(x + FIXED_RANDOM); }
+};
+
+
+
+struct TrieNode{ TrieNode* child[26]; bool isEnd;
+    TrieNode(){ isEnd = false; for(int i = 0; i<26; i++){ child[i] = NULL; } }
+};
+struct TrieNode* rootTrie;
+void addTrie(string& s){ TrieNode* curr = rootTrie; for(int i = 0; i<s.length(); i++){ int n = s[i] - 'a';if(curr->child[n] == NULL){curr->child[n] = new TrieNode();} curr = curr->child[n]; } curr->isEnd = true; }
+bool searchTrie(string& s){TrieNode* curr = rootTrie;for(int i = 0; i<s.length(); i++){int n = s[i] - 'a';if(!curr->child[n]) return false;curr = curr->child[n];}return curr->isEnd;}
+bool startsWithTrie(string s) {int n = s.length();TrieNode* curr = rootTrie;for(int i  =0 ; i<n; i++){int k = s[i] - 'a';if(curr->child[k] == NULL) return false;curr = curr->child[k];}return true;}
+
+
+
+int main(){
+//Jai Shree Ram
+    ios_base::sync_with_stdio(false);
+    cin.tie(NULL);
+    
+    string keys[] = {"the", "a", "there", "answer", "any", "by", "bye", "their" };
+    int n = sizeof(keys)/sizeof(keys[0]);
+    struct TrieNode *root = getNode();
+
+    for (int i = 0; i < n; i++) insert(root, keys[i]);
+ 
+    char output[][32] = {"Not present in trie", "Present in trie"};
+ 
+    cout<<"the"<<" --- "<<output[search(root, "the")]<<endl;
+    cout<<"these"<<" --- "<<output[search(root, "these")]<<endl;
+    cout<<"their"<<" --- "<<output[search(root, "their")]<<endl;
+    cout<<"thaw"<<" --- "<<output[search(root, "thaw")]<<endl;
+    return 0;
+}