From 8e119dad6d8210683068cfe11c5f6953a666e3cc Mon Sep 17 00:00:00 2001
From: Nitinpal07 <32491448+Nitinpal07@users.noreply.github.com>
Date: Mon, 2 Nov 2020 00:46:56 +0530
Subject: [PATCH 1/2] Create HuffmanEncoding.cpp

C++ implementation of HuffmanEncoding
---
 HuffmanEncoding.cpp | 76 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 76 insertions(+)
 create mode 100644 HuffmanEncoding.cpp

diff --git a/HuffmanEncoding.cpp b/HuffmanEncoding.cpp
new file mode 100644
index 0000000..82378fb
--- /dev/null
+++ b/HuffmanEncoding.cpp
@@ -0,0 +1,76 @@
+#include<bits/stdc++.h>
+using namespace std;
+
+class Node{
+    public:
+    char c;
+    int val;
+    Node* left;
+    Node* right;
+    Node(char c,int val){
+        this->c = c;
+        this->val = val;
+        left=right=NULL;
+    }
+};
+class mycomp
+{  public:
+    bool operator() (Node* a, Node* b)
+    {
+        return a->val>b->val;
+    }
+};
+
+Node* huffmancode(vector<pair<char,int>> a){
+   
+    priority_queue<Node*,vector<Node*>,mycomp> q;
+    for(int i=0;i<a.size();i++){
+        Node* newnode = new Node(a[i].first,a[i].second);
+        q.push(newnode);
+    }
+   
+    while(q.size()>1){
+        Node* top1 = q.top();
+        q.pop();
+        Node* top2 = q.top();
+        q.pop();
+        Node* newnode = new Node('#',top1->val+top2->val);
+        newnode->left = top1;
+        newnode->right = top2;
+        q.push(newnode);
+    }
+    Node* root = q.top();
+    q.pop();
+    return root;
+}
+
+void encode(Node* root,string s,map<char,string> &m){
+    if(root==NULL){
+        return;
+    }
+    if(root->left==NULL && root->right==NULL){
+        m[root->c] = s;
+    }
+    encode(root->left,s+"0",m);
+    encode(root->right,s+"1",m);
+}
+int main(){
+    int n;
+    cin>>n;
+    vector<pair<char,int>> a(n);
+    for(int i=0;i<n;i++){
+        char x;
+        int y;
+        cin>>x>>y;
+        a[i] = {x,y};
+    }
+    Node* root = huffmancode(a);
+    map<char,string> m;
+    string s = "";
+    encode(root,s,m);
+    for(auto i:m){
+        cout<<i.first<<"-->"<<i.second<<endl;
+    }
+    cout<<endl;
+    return 0;
+}

From c2d1478d399d22e7bc1d7c2e4c93de7afb9651b2 Mon Sep 17 00:00:00 2001
From: Nitinpal07 <32491448+Nitinpal07@users.noreply.github.com>
Date: Mon, 2 Nov 2020 01:11:41 +0530
Subject: [PATCH 2/2] Create HuffmanEncoding_Decoding.cpp

---
 HuffmanEncoding_Decoding.cpp | 94 ++++++++++++++++++++++++++++++++++++
 1 file changed, 94 insertions(+)
 create mode 100644 HuffmanEncoding_Decoding.cpp

diff --git a/HuffmanEncoding_Decoding.cpp b/HuffmanEncoding_Decoding.cpp
new file mode 100644
index 0000000..ead9d78
--- /dev/null
+++ b/HuffmanEncoding_Decoding.cpp
@@ -0,0 +1,94 @@
+#include<bits/stdc++.h>
+using namespace std;
+class Node{
+    public:
+    char c;
+    int val;
+    Node* left;
+    Node* right;
+    Node(char c,int val){
+        this->c = c;
+        this->val = val;
+        left=right=NULL;
+    }
+};
+class mycomp
+{  public:
+    bool operator() (Node* a, Node* b)
+    {
+        return a->val>b->val;
+    }
+};
+
+Node* huffmancode(vector<pair<char,int>> a){
+   
+    priority_queue<Node*,vector<Node*>,mycomp> q;
+    for(int i=0;i<a.size();i++){
+        Node* newnode = new Node(a[i].first,a[i].second);
+        q.push(newnode);
+    }
+   
+    while(q.size()>1){
+        Node* top1 = q.top();
+        q.pop();
+        Node* top2 = q.top();
+        q.pop();
+        Node* newnode = new Node('#',top1->val+top2->val);
+        newnode->left = top1;
+        newnode->right = top2;
+        q.push(newnode);
+    }
+    Node* root = q.top();
+    q.pop();
+    return root;
+}
+
+void encode(Node* root,string s,map<char,string> &m){
+    if(root==NULL){
+        return;
+    }
+    if(root->left==NULL && root->right==NULL){
+        m[root->c] = s;
+    }
+    encode(root->left,s+"0",m);
+    encode(root->right,s+"1",m);
+}
+int main(){
+    string s;
+    cin>>s;
+    
+    int n  = s.size();
+    map<char,int> m1;
+    for(int i=0;i<n;i++){
+        m1[s[i]]++;
+    }
+    vector<pair<char,int>> a;
+    for(auto i:m1){
+        a.push_back({i.first,i.second});
+    }
+    Node* root = huffmancode(a);
+    map<char,string> m;
+    string t = "";
+    encode(root,t,m);
+    map<string,char> decode;
+    for(auto i:m){
+        decode[i.second] = i.first;
+        cout<<i.first<<"-->"<<i.second<<endl;
+    }
+    cout<<"enter binary to code decode this string"<<endl;
+    string temp;
+    cin>>temp;
+    string run = "";
+    string ans="";
+    for(int i=0;i<temp.size();i++){
+        run.push_back(temp[i]);
+        if(decode.find(run)!=decode.end())
+        {
+            ans.push_back(decode[run]);
+            run = "";
+        }
+    }
+    cout<<ans<<endl;
+    cout<<endl;
+    return 0;
+}