Program to replace a word with asterisks in a sentence

For the given sentence as input, censor a specific word with asterisks ‘ * ‘. 
Example :

Input : word = “computer” 
text = “GeeksforGeeks is a computer science portal for geeks. People who love computer and computer codes can contribute their valuables/ideas on computer codes/structures on here.” 
Output : GeeksforGeeks is a ******** science portal for geeks. People who love ******** and ******** codes can contribute their valuables/ideas on ******** codes/structures on here.

The idea is to first split given sentence into different words. Then traverse the word list. For every word in the word list, check if it matches with given word. If yes, then replace the word with stars in the list. Finally merge the words of list and print. 

C++

// C++ program to censor a word
// with asterisks in a sentence
#include<bits/stdc++.h>
#include <boost/algorithm/string.hpp>
using namespace std;

// Function takes two parameter
string censor(string text,
                    string word)
{

    // Break down sentence by ' ' spaces
    // and store each individual word in
    // a different list
    vector<string> word_list;
    boost::split(word_list, text, boost::is_any_of("\\ +"));

    // A new string to store the result
    string result = "";

    // Creating the censor which is an asterisks
    // "*" text of the length of censor word
    string stars = "";
    for (int i = 0; i < word.size(); i++)
        stars += '*';

    // Iterating through our list
    // of extracted words
    int index = 0;
    for (string i : word_list)
    {

        if (i.compare(word) == 0)
        {

            // changing the censored word to
            // created asterisks censor
            word_list[index] = stars;
        }
        index++;
    }

    // join the words
    for (string i : word_list)
    {
        result += i + ' ';
    }
    return result;
}

// Driver code
int main()
{
    string extract = "GeeksforGeeks is a computer science "
                    "portal for geeks. I am pursuing my "
                    "major in computer science. ";
    string cen = "computer";
    cout << (censor(extract, cen));
}

// This code is contributed by Rajput-Ji

Java

// Java program to censor a word
// with asterisks in a sentence
class GFG
{

// Function takes two parameter
static String censor(String text,
                     String word)
{

    // Break down sentence by ' ' spaces
    // and store each individual word in
    // a different list
    String[] word_list = text.split("\\s+");

    // A new string to store the result
    String result = "";

    // Creating the censor which is an asterisks
    // "*" text of the length of censor word
    String stars = "";
    for (int i = 0; i < word.length(); i++)
        stars += '*';

    // Iterating through our list
    // of extracted words
    int index = 0;
    for (String i : word_list)
    {
        if (i.compareTo(word) == 0)

            // changing the censored word to
            // created asterisks censor
            word_list[index] = stars;
        index++;
    }

    // join the words
    for (String i : word_list)
        result += i + ' ';

    return result;
}

// Driver code
public static void main(String[] args)
{
    String extract = "GeeksforGeeks is a computer science "+
                     "portal for geeks. I am pursuing my " +
                     "major in computer science. ";
    String cen = "computer";
    System.out.println(censor(extract, cen));
}
}

// This code is contributed by
// sanjeev2552

Python3

# Python Program to censor a word
# with asterisks in a sentence


# Function takes two parameter
def censor(text, word):

    # Break down sentence by ' ' spaces
    # and store each individual word in
    # a different list
    word_list = text.split()

    # A new string to store the result
    result = ''

    # Creating the censor which is an asterisks
    # "*" text of the length of censor word
    stars = '*' * len(word)

    # count variable to
    # access our word_list
    count = 0

    # Iterating through our list
    # of extracted words
    index = 0;
    for i in word_list:

        if i == word:

            # changing the censored word to
            # created asterisks censor
            word_list[index] = stars
        index += 1

    # join the words
    result =' '.join(word_list)

    return result

# Driver code
if __name__== '__main__':

    extract = "GeeksforGeeks is a computer science portal for geeks.\
               I am pursuing my major in computer science. "
    cen = "computer"
    print(censor(extract, cen))

C#

// C# program to censor a word
// with asterisks in a sentence
using System;
using System.Collections.Generic;

class GFG
{

// Function takes two parameter
static String censor(String text,
                     String word)
{

    // Break down sentence by ' ' spaces
    // and store each individual word in
    // a different list
    String[] word_list = text.Split(' ');

    // A new string to store the result
    String result = "";

    // Creating the censor which is an asterisks
    // "*" text of the length of censor word
    String stars = "";
    for (int i = 0; i < word.Length; i++)
        stars += '*';

    // Iterating through our list
    // of extracted words
    int index = 0;
    foreach (String i in word_list)
    {
        if (i.CompareTo(word) == 0)

            // changing the censored word to
            // created asterisks censor
            word_list[index] = stars;
        index++;
    }

    // join the words
    foreach (String i in word_list)
        result += i + " ";

    return result;
}

// Driver code
public static void Main(String[] args)
{
    String extract = "GeeksforGeeks is a computer science "+
                     "portal for geeks. I am pursuing my " +
                     "major in computer science. ";
    String cen = "computer";
    Console.WriteLine(censor(extract, cen));
}
}

// This code is contributed by PrinciRaj1992

PHP

<?php
// PHP Program to censor a word
// with asterisks in a sentence

// Function takes two parameter
function censor($text, $word)
{

    // Break down sentence by ' ' spaces
    // and store each individual word in
    // a different list
    $word_list = explode(" ", $text);

    // A new string to store the result
    $result = '';

    // Creating the censor which is an
    // asterisks "*" text of the length
    // of censor word
    $stars = "";
    for($i = 0; $i < strlen($word); $i++)
    $stars .= "*";

    // count variable to access
    // our word_list
    $count = 0;

    // Iterating through our list of
    // extracted words
    $index = 0;
    for($i = 0; $i < sizeof($word_list); $i++)
    {
        if($word_list[$i] == $word)

            // changing the censored word to
            // created asterisks censor
            $word_list[$index] = $stars;
        $index += 1;
    }

    // join the words
    return implode(' ', $word_list);
}

// Driver code
$extract = "GeeksforGeeks is a computer science ".
           "portal for geeks.\nI am pursuing my ".
                    "major in computer science. ";
$cen = "computer";
echo censor($extract, $cen);

// This code is contributed
// by Aman ojha
?>

Javascript

<script>

      // JavaScript program to censor a word
      // with asterisks in a sentence

      // Function takes two parameter
      function censor(text, word) {
        // Break down sentence by ' ' spaces
        // and store each individual word in
        // a different list
        var word_list = text.split(" ");

        // A new string to store the result
        var result = "";

        // Creating the censor which is an asterisks
        // "*" text of the length of censor word
        var stars = "";
        for (var i = 0; i < word.length; i++) stars += "*";

        // Iterating through our list
        // of extracted words
        var index = 0;
        for (const i of word_list) {
          if (i === word)
            // changing the censored word to
            // created asterisks censor
            word_list[index] = stars;
          index++;
        }

        // join the words
        for (const i of word_list) {
          result += i + " ";
        }

        return result;
      }

      // Driver code
      var extract =
        "GeeksforGeeks is a computer science " +
        "portal for geeks. I am pursuing my " +
        "major in computer science. ";

      var cen = "computer";
      document.write(censor(extract, cen) + "<br>");

</script>

Output:

GeeksforGeeks is a ******** science portal for geeks.
I am pursuing my major in ******** science.

Time complexity: O(length(word)+M)

where M is the number of words in text

Auxiliary Space: O(1)