Question

I want the code below to be edited:

Rather than giving the input string inside the code, I want the program to ask the user for an input and calculate and complete this code.
I have pasted the actual code below, Please edit the input section only so that I can input any string or any sentence as I like. The program must ask the user that "Enter a string/sentence" and take the data to calculate the Huffman code.

#include <bits/stdc++.h> 
#define MAX_TREE_HT 256 
using namespace std; 

map<char, string> codes; 

map<char, int> freq; 

struct MinHeapNode 
{ 
    char data;          
    int freq;           
    MinHeapNode *left, *right; 
  
    MinHeapNode(char data, int freq) 
    { 
        left = right = NULL; 
        this->data = data; 
        this->freq = freq; 
    } 
}; 

struct compare 
{ 
    bool operator()(MinHeapNode* l, MinHeapNode* r) 
    { 
        return (l->freq > r->freq); 
    } 
}; 

void printCodes(struct MinHeapNode* root, string str) 
{ 
    if (!root) 
        return; 
    if (root->data != '$') 
        cout << root->data << ": " << str << "\n"; 
    printCodes(root->left, str + "0"); 
    printCodes(root->right, str + "1"); 
} 

void storeCodes(struct MinHeapNode* root, string str) 
{ 
    if (root==NULL) 
        return; 
    if (root->data != '$') 
        codes[root->data]=str; 
    storeCodes(root->left, str + "0"); 
    storeCodes(root->right, str + "1"); 
} 
  
priority_queue<MinHeapNode*, vector<MinHeapNode*>, compare> minHeap; 

void HuffmanCodes(int size) 
{ 
    struct MinHeapNode *left, *right, *top; 
    for (map<char, int>::iterator v=freq.begin(); v!=freq.end(); v++) 
        minHeap.push(new MinHeapNode(v->first, v->second)); 
    while (minHeap.size() != 1) 
    { 
        left = minHeap.top(); 
        minHeap.pop(); 
        right = minHeap.top(); 
        minHeap.pop(); 
        top = new MinHeapNode('$', left->freq + right->freq); 
        top->left = left; 
        top->right = right; 
        minHeap.push(top); 
    } 
    storeCodes(minHeap.top(), ""); 
} 

void calcFreq(string str, int n) 
{ 
    for (int i=0; i<str.size(); i++) 
        freq[str[i]]++; 
} 

string decode_file(struct MinHeapNode* root, string s) 
{ 
    string ans = ""; 
    struct MinHeapNode* curr = root; 
    for (int i=0;i<s.size();i++) 
    { 
        if (s[i] == '0') 
           curr = curr->left; 
        else
           curr = curr->right; 
  
        if (curr->left==NULL and curr->right==NULL) 
        { 
            ans += curr->data; 
            curr = root; 
        } 
    } 
    return ans+'\0'; 
} 
  
int main() 
{ 
    string str = "Please remove this input and help me put my own input into the program"; 
    string encodedString, decodedString; 
    calcFreq(str, str.length()); 
    HuffmanCodes(str.length()); 

    cout << "Character With there Frequencies:\n"; 
    for (auto v=codes.begin(); v!=codes.end(); v++) 
        cout << v->first <<' ' << v->second << endl; 
  
    for (auto i: str) 
        encodedString+=codes[i]; 
  
    cout << "\nEncoded Huffman data:\n" << encodedString << endl; 
  
    decodedString = decode_file(minHeap.top(), encodedString); 
    cout << "\nDecoded Huffman Data:\n" << decodedString << endl; 
    return 0; 
}

Answer 1

#include <bits/stdc++.h> 
#define MAX_TREE_HT 256 
using namespace std; 

map<char, string> codes; 

map<char, int> freq; 

struct MinHeapNode 
{ 
    char data;          
    int freq;           
    MinHeapNode *left, *right; 
  
    MinHeapNode(char data, int freq) 
    { 
        left = right = NULL; 
        this->data = data; 
        this->freq = freq; 
    } 
}; 

struct compare 
{ 
    bool operator()(MinHeapNode* l, MinHeapNode* r) 
    { 
        return (l->freq > r->freq); 
    } 
}; 

void printCodes(struct MinHeapNode* root, string str) 
{ 
    if (!root) 
        return; 
    if (root->data != '$') 
        cout << root->data << ": " << str << "\n"; 
    printCodes(root->left, str + "0"); 
    printCodes(root->right, str + "1"); 
} 

void storeCodes(struct MinHeapNode* root, string str) 
{ 
    if (root==NULL) 
        return; 
    if (root->data != '$') 
        codes[root->data]=str; 
    storeCodes(root->left, str + "0"); 
    storeCodes(root->right, str + "1"); 
} 
  
priority_queue<MinHeapNode*, vector<MinHeapNode*>, compare> minHeap; 

void HuffmanCodes(int size) 
{ 
    struct MinHeapNode *left, *right, *top; 
    for (map<char, int>::iterator v=freq.begin(); v!=freq.end(); v++) 
        minHeap.push(new MinHeapNode(v->first, v->second)); 
    while (minHeap.size() != 1) 
    { 
        left = minHeap.top(); 
        minHeap.pop(); 
        right = minHeap.top(); 
        minHeap.pop(); 
        top = new MinHeapNode('$', left->freq + right->freq); 
        top->left = left; 
        top->right = right; 
        minHeap.push(top); 
    } 
    storeCodes(minHeap.top(), ""); 
} 

void calcFreq(string str, int n) 
{ 
    for (int i=0; i<str.size(); i++) 
        freq[str[i]]++; 
} 

string decode_file(struct MinHeapNode* root, string s) 
{ 
    string ans = ""; 
    struct MinHeapNode* curr = root; 
    for (int i=0;i<s.size();i++) 
    { 
        if (s[i] == '0') 
           curr = curr->left; 
        else
           curr = curr->right; 
  
        if (curr->left==NULL and curr->right==NULL) 
        { 
            ans += curr->data; 
            curr = root; 
        } 
    } 
    return ans+'\0'; 
} 
  
int main() 
{ 
    string str; 
    cout<<"Enter a string/sentence"<<endl;
    getline(cin,str);
    
    string encodedString, decodedString; 
    calcFreq(str, str.length()); 
    HuffmanCodes(str.length()); 

    cout << "Character With there Frequencies:\n"; 
    for (auto v=codes.begin(); v!=codes.end(); v++) 
        cout << v->first <<' ' << v->second << endl; 
  
    for (auto i: str) 
        encodedString+=codes[i]; 
  
    cout << "\nEncoded Huffman data:\n" << encodedString << endl; 
  
    decodedString = decode_file(minHeap.top(), encodedString); 
    cout << "\nDecoded Huffman Data:\n" << decodedString << endl; 
    return 0; 
}

I have edited the code as required. Now it asks user for the input.