Remove a Given Word from a String using C++

In this article, we’ll be solving the problem of removing a given word from a given string. For example −

Input : str = “remove a given word ”, word = “ remove ”
Output : “ a given word ”

Input : str = “ god is everywhere ”, word = “ is ”
Output : “ god everywhere ”

Approach to find The Solution

For example, we can use a simple approach to remove a word from a string.

• First, put the given string in 2-D matrix form, where each word is stored in each row.
• Find the word in the matrix and replace that row with the null character where the word.
• Finally, print the reordered string.

Example

#include <bits/stdc++.h>
using namespace std;
int remove_word (string str, char word[]) {
   char matrix[10][30];
   int i = 0, j = 0, k = 0, len1 = 0, len2 = 0;

   // putting each word of string into the rows of the 2-D matrix.
   for (i = 0; str[i] != '\0'; i++) {
      if (str[i] == ' ') {
         matrix[k][j] = '\0';
         k++;
         j = 0;
      }else{
         matrix[k][j] = str[i];
         j++;
      }
   }
   // looking for the word in a given string and putting a null character when the word is found.
   matrix[k][j] = '\0';
   j = 0;
   for (i = 0; i < k + 1; i++) {
      if (strcmp (matrix[i], word) == 0) {
         matrix[i][j] = '\0';
      }
   }

   j = 0;
   // printing the reordered string.
   for (i = 0; i < k + 1; i++){
      if (matrix[i][j] == '\0')
         continue;
      else
         cout << matrix[i] << " ";
   }

   cout << "\n";
}

int main () {
   char str1[] = "remove a given word", word1[] = "remove";
   char str2[] = "god is everywhere", word2[]="is";
   // calling a function to remove a word from a string and print it.
   remove_word (str1, word1);
   remove_word (str2, word2);

   return 0;
}

Output

a given word
god everywhere

Explanation of the above code

• Initializing string and array with some values and calling function to remove given the word.
• Putting each word of string in each row of a 2-D matrix using a loop stored each character in each block until space is found.
• Comparing string with a word using strcmp() function and put null value in the row where the word is found.
• Finally, printing the string with printing each row of the matrix.

Conclusion

This article discussed removing a given word from a String where we solve the problem by storing the string in a 2-D matrix and then replacing the word with a null value. We solved this problem using C++ code. However, we can solve the same problem using any other language like C, Java, Python, etc. Hope you find this article helpful.