Source of revline4.cpp

Structures and functions

  1: // Filename: REVLINE4.CPP
  2: // Purpose:  Reads in a line of input and then writes out
  3: //           the line with all characters in reverse order.

  5: #include <iostream>
  6: using namespace std;

  8: void ReadRestOfCharsAndWriteInReverse();

 10: int main()
 11: {
 12:     cout << endl;

 14:     cout << "This program reads a sentence and "
 15:          << "then writes it out in reverse order."     << endl;
 16:     cout << endl;

 18:     cout << "Enter a sentence on the following line: " << endl;
 19:     ReadRestOfCharsAndWriteInReverse();

 21:     cout << endl << endl;

 23:     return 0;
 24: }


 27: void ReadRestOfCharsAndWriteInReverse()
 28: // Pre:  The standard input stream is empty.
 29: // Post: All characters entered by the user, up to the
 30: //       first newline character, have been read in and
 31: //       writen out in reverse order.
 32: {
 33:     char ch;

 35:     if (cin.peek() == '\n')  // Note use of cin.peek()
 36:         ;                    // to "look ahead" one character.
 37:     else
 38:     {
 39:         cin.get(ch);
 40:         ReadRestOfCharsAndWriteInReverse();
 41:         cout << ch;
 42:     }
 43: }