string metin;
metin = Console.ReadLine();
for (int i = metin.Length-1; i >= 0 ;i-- )
Console.Write(metin[i]);

string yazi = "yazı";
char[] ters = new char[yazi.Length];
for (int i = 0; i < yazi.Length / 2; ++i)
{
ters[i] = yazi[yazi.Length - i - 1];
ters[yazi.Length - i - 1] = yazi[i];
}
if (yazi.Length % 2 == 1)
ters[yazi.Length / 2] = yazi[yazi.Length / 2];
Console.WriteLine(ters);