{$zerobasedstrings}
const
n = 3;
m = 2;
begin
var s := '0123456789';
Writeln(s.Substring(n, m));
Writeln(s[n:]);
Writeln(s[:^1]);
Writeln(s.Substring(s.IndexOf('3'), m));
Writeln(s.Substring(s.IndexOf('456'), m));
end.