Write a program that asks the user to enter a sentence and uses a regular expression to check whether the sentence contains more than one space between words. If so, the program should remove the extra spaces. For example, the string "Hello World" should be "Hello World".

Question

What will be an ideal response?

Answer 1

```
#include
#include
#include
using namespace std;

int main()
{ string sentence;

// get the sentence from the user
cout << "Please enter a sentence: ";
getline( cin, sentence );

// check for extra spaces
if ( !( boost::regex_search( sentence, boost::regex( "\\s{2,}" ) ) ) )
cout << "No extra spaces!" << endl;
else
{
// replace any occurrences of multiple spaces with a single space
sentence =
boost::regex_replace( sentence, boost::regex( "\\s{2,}" ), " " );

// display the corrected sentence
cout << "All extra spaces have been removed.\n" << sentence;
} // end else

cout << endl;
} // end main
```
Please enter a sentence: This sentence has too many spaces
All extra spaces have been removed.
This sentence has too many spaces