how to replace every match of a charecter in the entire string?? in c++

Question

this my code when i give the input of aeiou AEIOU it only out puts xxxxx where did i go wrong??? i want to replace every vowel in the entire string but i only does it for the first word is my code wrong ??

#include<iostream>                                                                                                                                    
#include<string>                                                                                                                                      
#include<algorithm>                                                                                                                                   

using namespace std;                                                                                                                                  

class remove_vowels_class                                                                                                                             
{                                                                                                                                                     
 private:                                                                                                                                             

 public:                                                                                                                                              

    void remove_vowels_accept(string the_string)                                                                                                      
    {                                                                                                                                                   
      std::replace(the_string.begin(),the_string.end(),'a','x');                                                                                      
      std::replace(the_string.begin(),the_string.end(),'A','x');                                                                                      
      std::replace(the_string.begin(),the_string.end(),'e','x');                                                                                          
      std::replace(the_string.begin(),the_string.end(),'E','x');                                                                                      
      std::replace(the_string.begin(),the_string.end(),'i','x');                                                                                        
      std::replace(the_string.begin(),the_string.end(),'I','x');                                                                                      
      std::replace(the_string.begin(),the_string.end(),'o','x');                                                                                      
      std::replace(the_string.begin(),the_string.end(),'O','x');                                                                                         
      std::replace(the_string.begin(),the_string.end(),'u','x');                                                                                      
      std::replace(the_string.begin(),the_string.end(),'U','x');                                                                                      
      std::replace(the_string.begin(),the_string.end(),'~',' ');                                                                                      
      cout<<"the replaced string is :"<<the_string<<endl;                                                                                             

  }                                                                                                                                                   
};                                                                                                                                                    

int main()                                                                                                                                          
  {                                                                                                                                                   
remove_vowels_class maniobj;                                                                                                                      
string input_string;                                                                                                                              
cout<< "Enter a string to replace all vowels:"<<endl;                                                                                             
cin>>input_string;                                                                                                                                
std::replace(input_string.begin(),input_string.end(),' ','~');                                                                                    
maniobj.remove_vowels_accept(input_string);

Did you really need to put the Emacs mode line in the question? — Barmar, Jan 09 '14 at 16:48

James Reed · Accepted Answer · 2014-01-09T16:56:14.630

4

cin>>input_string; will extract text from the input until it reaches whitespace, so only the first word of your input will be put into input_string. Use std::getline in the string library to get a whole line.

edited Jan 09 '14 at 16:56

answered Jan 09 '14 at 16:47

James Reed

491
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score 2 · Answer 2 · answered Jan 09 '14 at 16:50

2

Use std::getline instead of cin>>input_string

cin>>input_sting will only read input string till space.

std::getline( std::cin, input_string);

answered Jan 09 '14 at 16:50

Digital_Reality

4,488
1
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score 1 · Answer 3 · edited May 23 '17 at 12:28

1

Just like scanf, cin ignores whitespaces. Check this out. Try gets http://www.cplusplus.com/reference/cstdio/gets/ in order to read the string.

EDIT: As @James Reed pointed out, gets is getting removed from the standard. Another answer has provided an alternative. I'm leaving the answer though for future reference.

edited May 23 '17 at 12:28

Community

1
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answered Jan 09 '14 at 16:49

rhobincu

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1

`gets` is deprecated as of C++11. You shouldn't be using C-strings in C++ unless you have to, anyway. – James Reed Jan 09 '14 at 16:52

score 0 · Answer 4 · answered Jan 09 '14 at 17:04

You need to use std::getline, here's a cleaner / simpler c++11 implementation.

#include <string>
#include <iostream>

std::string replace_vowels(const std::string & str) {
    static const char vowels[] = {'a', 'A', 'e', 'E', 'i', 'I', 'o', 'O', 'u', 'U'};
    std::string cp(str);
    for(std::size_t i = 0; i < str.length(); ++i) {
        auto & ch = str[i];
        for(auto & v : vowels) {
            if(ch == v) {
                cp[i] = 'x';
                break;
            }
        }
    }
    return std::move(cp);
}

int main() {
    std::string input, output;
    std::cout << "Enter a string to replace all vowels : ";
    std::getline(std::cin, input);
    output = replace_vowels(input);
    std::cout << "Input : " << input << " / Output : " << output << std::endl;
}

how to replace every match of a charecter in the entire string?? in c++

4 Answers4