2_5_4.cpp

#include <iostream>
#include <string>

// say what standard-library we use
using std::cin;    using std::endl; using std::cout; using std::string;

int main()
{
  // ask for the person's name
  cout << "Please enter your first name: ";

  // read the name
  string name;
  cin >> name;

  // build the message that we intend to write
  const string greeting = "Hello, " + name + "!";

  // the number of blanks surrounding the greeting
  int pad = 1;

  // get user input for padding
  cout << "How much padding do you want? ";
  cin >> pad;

  // the number of rows and columns to write
  const int rows = pad * 2 + 3;
  const string::size_type cols = greeting.size() + pad * 2 + 2;

  // write a blank line to separate the output from the input
  cout << endl;

  // construct blanklines
  const string spaces(greeting.size() + pad * 2, ' ');
  const string blankline = "*" + spaces + '*';

  // write rows rows of output
  // invariant: we have written r rows so far
  for (int r = 0; r != rows; ++r){
    string::size_type c = 0;

    // invatiant: we have written c characters so far in the current row
    while (c != cols){
      // is it time to write the greeting?
      if (r == pad + 1 && c == pad + 1) {
	cout << greeting;
	c += greeting.size();
      } else {
	// are we on the border?
	if (r == 0 || r == rows - 1 || c == 0 || c == cols -1)
	  cout << "*";
	else
	  cout << " ";
	++c;
      }
    }
    cout << endl;
  }
  return 0;
}