Bài này mình có làm rồi nên đưa code luôn nha 

//////////////////////////////////////////////////////////

var a:array[0..255] of string;
    s,z,m,st,t:string;
    i,k,ma,dem,x,y,d,c,n:longint;
begin
readln(s);
st := copy(s,1,length(s));
read(k);
ma := 0;
s := s + #32;
d := 0;
while length(s) <> 0 do
 begin
       x := pos(#32,s);
       y := x - 1;
       z := copy(s,1,y);
       inc(d);
       a[d] := z;
       delete(s,1,x);
 end;
for i := 1 to d do
 if (length(a[i]) > ma) then
   begin
       ma := length(a[i]);
       c := 1;
   end
 else if ma = length(a[i]) then inc(c);
writeln(c);
n := length(st);
for i := 1 to n + 1 do
 if (st[i] <> #32) and (i <> n + 1) then t := t + st[i]
  else
    begin
        if length(t) > length(m) then m := t; t :='';
    end;
n := length(m);
for i := 1 to n do
  if (ord(m[i])>64)and(ord(m[i])<91) then
   if (ord(m[i])-k<65) then write(chr(ord(s[i]) - k + 26))
    else write(chr(ord(m[i])-k));
readln;readln; 
end.