Program NhatNgu;
Uses crt;
Var a,b,i: longint;

Function shh(m: longint): boolean;
Var s,i: longint;
Begin
        s:=0;
        For i:=1 to m div 2 do
                If m mod i = 0 then s:=s+i;
        If s=m then exit(true);
        exit(false);
End;

Begin
        Clrscr;
        Write('Nhap a: '); Readln(a);
        Write('Nhap b: '); Readln(b);
        For i:=a to b do
                If shh(i) then Write(i,' ');
        Readln
End.

Program vd;uses crt;var n,p:LongInt;Function kt(a:LongInt):Boolean;var i:LongInt;BeginIf a<2 then exit(false);For i:=2 to trunc(sqrt(a)) do If a mod i=0 then exit(false);exit(true);end;Beginclrscr;Write('Du lieu vao: ');Readln(n);If (n<=0) or (n>1000000) then begin Writeln('DU LIEU SAI'); Readln; halt; end;If n=2 then begin Writeln('No'); Readln; halt; end;p:=(n-1) div 2;If (kt(n)=true) and (kt(p)=true) then Writeln('Yes') else Writeln('No');Readln;end.