Trie having method for insertion, deletion, searching and printing contents of it

Author: vikesh8860

Data Structures/Trie/tries_using_map.cpp

@@ -0,0 +1,146 @@
+#include <bits/stdc++.h>
+#define ll long long int
+using namespace std;
+struct node
+{
+    bool word_end;
+    map<char,node*> m;
+};
+node* getnode(){
+    node* temp = new node;
+    temp->word_end =false;
+    temp->m = map<char,node*>();
+    return temp;
+}
+node* insert(node* start,string s){
+    int i=0,n=s.size();
+    for(i=0;i<n;i++)
+    {
+        map<char,node*>::iterator it = start->m.find(s[i]);
+        if(it==start->m.end())
+        {
+            node* temp = getnode();
+            start->m.insert(make_pair(s[i],temp));
+            start = temp;
+        }
+        else
+            start = (*it).second;
+    }
+    start->word_end = true;
+}
+bool find(node* start,string s){
+    int i=0,n=s.size();
+    for(i=0;i<n;i++)
+    {
+        map<char,node*>::iterator it = start->m.find(s[i]);
+        if(it==start->m.end())
+            return false;
+        start = (*it).second;
+    }
+    if(start->word_end==true)
+        return true;
+    else 
+        return false;
+}
+bool delete_util(node* start,string s,int begin,int end){
+    if(begin==end)
+    {
+        if(!start->word_end)
+            return false;
+        else
+        {
+            if(!start->m.size())
+            {
+                free(start);
+                return true;
+            }
+            else
+                start->word_end = false;
+        }
+    }
+    else
+    {
+        map<char,node*>::iterator it = start->m.find(s[begin]);
+        if(it==start->m.end())
+            return false;
+        bool temp = delete_util((*it).second,s,begin+1,end);
+        if(temp==false)
+            return false;
+        else
+        {
+            start->m.erase(s[begin]);
+            if(start->m.size()==0)
+            {
+                free(start);
+                return true;
+            }
+            else
+                return false;
+        }
+    }
+}
+void delete_node(node* start,string s){
+    delete_util(start,s,0,s.size());
+}
+void level_order(node* start){
+    queue<node*> q;
+    q.push(start);
+    q.push(getnode());
+    while(!q.empty())
+    {
+        node* temp = q.front();
+        q.pop();
+        if(temp->m.size()==0)
+        {
+            if(q.empty())
+                break;
+            cout<<"\n";
+            q.push(temp);
+        }
+        else
+        {
+            map<char,node*>::iterator it = temp->m.begin();
+            for(it;it!=temp->m.end();it++)
+            {
+                cout<<(*it).first;
+                node* t = (*it).second;
+                if(t->m.size()>0)
+                    q.push(t);
+            }
+            cout<<" ";
+        }
+    }
+}
+void print_words(node* start,string s){
+    if(start->m.size()==0){
+        if(s.size()!=0)
+            cout<<s<<"  ";
+    }
+    for(map<char,node*>::iterator it=start->m.begin();it!=start->m.end();it++)
+        print_words((*it).second,s+(*it).first);
+}
+int main() 
+{
+    node* start = getnode();
+    int t;
+    cin>>t;
+    string s;
+    while(t--)
+    {
+        cin>>s;
+        insert(start,s);
+    }
+    //level_order(start);
+	
+    //To find a something in the trie
+	//cout<<find(start,"william")<<"\n";
+	
+	//To delete from trie
+    //delete_node(start,"wilsoni");
+    
+	//To print all the data from trie
+	//print_words(start,"");
+	
+	return 0;
+}
+