huffman.cpp

huffman.cpp

@@ -0,0 +1,111 @@
+#include<iostream>
+#include<queue>
+using namespace std;
+
+struct Node
+{
+    int freq;
+    char ch;
+    Node* left,*right;
+
+    Node(int f, char c, Node* l=NULL, Node* r=NULL)
+    {
+        freq=f;
+        ch=c;
+        left=l;
+        right=r;
+    }
+};
+
+struct compare
+{
+    bool operator()(Node* l , Node* r)
+    {
+        return l->freq > r->freq;
+    }
+};
+
+
+void printCodes(Node* root, string str="")
+{
+    if(root->ch != '$')
+    {
+        cout<<root->ch<<"  "<<str<<"\n";
+        return;
+    }
+
+    printCodes(root->left, str+"0");
+    printCodes(root->right, str+"1");
+}
+
+void printHCodes(char arr[], int freq[], int n)
+{
+    priority_queue<Node*, vector<Node*> , compare> h;
+
+    for(int i=0; i<n;i++)
+    {
+        h.push(new Node(freq[i],arr[i]));
+    }
+
+    while( h.size() > 1)
+    {
+        Node* l = h.top();
+
+        h.pop();
+
+        Node* r = h.top();
+
+        h.pop();
+
+        Node* node = new Node(l->freq+r->freq,'$',l,r);
+
+        h.push(node);
+    }
+
+    printCodes(h.top());
+}
+
+/*struct compare
+{
+
+    bool operator()(Node* l , Node* r)
+    {
+        return l->freq > r->freq;
+    }
+};*/
+
+
+
+int main()
+{
+    int n;
+
+    cout<<"Enter the number of distinguished characters : "<<endl;
+    cin>>n;
+
+    char arr[n];
+    int freq[n];
+
+    for(int i=0;i<n;i++)
+    {
+        cout<<"Character "<<(i+1)<<" : ";
+        cin>>arr[i];
+
+        cout<<"Frequncy "<<(i+1)<<" : ";
+        cin>>freq[i];
+    }
+
+    cout<<"CHARACTERS AND THEIR FREQUENCIES : "<<endl;
+    for(int i=0;i<n;i++)
+    {
+        cout<<arr[i]<<"\t"<<freq[i]<<endl;
+    }
+
+
+    cout<<"Characters and their codes : "<<endl;
+    printHCodes(arr, freq, n);
+
+
+    return 0;
+}
+