Cách 1: dùng xâu phụ:
uses crt;
var s,s1:string; c:char;
begin
clrscr;
write('Nhap mot xau: ');readln(s1);
s:=s1;
c:=s[1]; s[1]:=s[length(s)]; s[length(s)]:=c;
writeln(s1,'->',s);
readln;
end.
Cách 2: không dùng xâu phụ:
uses crt;
var s:string;
begin
clrscr;
write('Nhap mot xau: ');readln(s);
writeln(s,'->',s[length(s)],copy(s,2,length(s)-2),s[1]);
readln;
end.