#include <iostream>
#include <string>
 
using namespace std;
 
void ReverseString(string &S, int start, int end)
{
   if ( start < end )
   {
      swap(S[start], S[end - 1]);
      ReverseString(S, start+1, end - 1);
   }
}
 
void ReverseString(string &S)
{
   ReverseString(S, 0, S.size());
}
 
int main()
{
    string s = "The string to reverse" ;
 
    cout << "Before Reversing" << endl;
    cout << s << endl;
 
    ReverseString(s);
    cout << "After Reversing" << endl;
    cout << s << endl;
 
    ReverseString(s, 0, 7);
    cout << "After Reversing a subset" << endl;
    cout << s << endl;
    return 0;
}
 

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