Phan1 {Hoan vi}

var

s:string;

function next (A:string):string;

var

n,i,j:integer;

c:char;

begin

n:=length (s);

i:=n-1;

while ((i>0) and (a[i]>a[i+1])) do i:=i-1;

if i=0 then next:='!'

else

begin

j:=n;

while a[j]<a[i] do

j:=j-1;

c:=a[i];

a[i]:=a[j];

a[j]:=c;

for j:=i+1 to (n+i+1)div 2 do

begin

c:=a[j];

a[j]:=a[n+i+1-j];

a[n+i+1-j]:=c;

end;

next:=A;

end;

end;

begin

write('nhap s=');

readln(s);

while (s<> '!') do

begin

write(s:8);

s:= next(s);

end;

readln;

end.

-----------------------------------------------------------------

//phan 2

var

s:string;

function next (A:string):string;

var

n,i,j:integer;

c:char;

begin

n:=length (s);

i:=n-1;

while ((i>0) and (a[i]>a[i+1])) do i:=i-1;

if i=0 then next:='!'

else

begin

j:=n;

while a[j]<a[i] do

j:=j-1;

c:=a[i];

a[i]:=a[j];

a[j]:=c;

for j:=i+1 to (n+i+1)div 2 do

begin

c:=a[j];

a[j]:=a[n+i+1-j];

a[n+i+1-j]:=c;

end;

next:=A;

end;

end;

begin

write('nhap s=');

readln(s);

while (s<> '!') do

begin

write(s:8);

s:= next(s);

end;

readln;

end.