{$codepage utf8} Var a:qword; b:int64; Begin a:=18446744073709551615; a:=a+1; Writeln(a); //0 a:=a-1; Writeln(a); //18446744073709551615 b:=9223372036854775807; b:=b+1; Writeln(b); //-9223372036854775808 b:=b-1; Writeln(b) //9223372036854775807 End.