As somebody will undoubtedly mention eventually, if you can use the STL then it all becomes dead simple.

Code:
#include <string>
#include <algorithm>
#include <iostream>

using namespace std;

int  main()
{
	const string s1("Tony");

        string s2(s1);

        reverse(s2.begin(), s2.end());

	cout << s2 << endl;

	return 0;
}