import std.stdio, std.algorithm, std.conv, std.string, std.array, std.math;

void main()
{
  readln;
  const s = readln.chomp;
  if (s.length%2 == 0 && s[0..$/2] == s[$/2..$]) {
    "Yes".writeln;
    return;
  }
  "No".writeln;
}