function TdmData.AlgoCesar(decalage:integer;texte:string):string;
var tmp:string;
    i:integer;
begin
  tmp:='';
  for i:=1 to length(texte) do
    begin
      tmp:=tmp+chr(ord(texte[i])+decalage);
    end;
  AlgoCesar:=tmp;
end;

function TdmData.VigenereCrypt(texte:string):string;
var i,nb:integer;
    tmp,password:string;
begin
  tmp:='';
  nb:=1;
  password := 'MYPSS';
  for i:=1 to length(texte) do
    begin
      tmp:=tmp+chr(ord(texte[i])+ord(password[nb]));
      nb:=nb+1;
      if nb>length(password) then
        begin
          nb:=1;
        end;
    end;
  VigenereCrypt:=tmp;
end;

function TdmData.VigenereDecrypt(texte:string):string;
var i,nb:integer;
    tmp,password:string;
begin
  tmp:='';
  password := 'MYPSS';
  nb:=1;
  for i:=1 to length(texte) do
    begin
      tmp:=tmp+chr((ord(texte[i])+256)-ord(password[nb]));
      nb:=nb+1;
      if nb>length(password) then
        begin
          nb:=1;
        end;
    end;
  VigenereDecrypt:=tmp;
end;