program calculation;
uses crt;
var a,b, c, d, Res:integer;
begin
clrscr;
writeln('Enter  1 number');
readln(a);
writeln('Enter 2 number');
readln(b);
writeln('Enter  3 number');
readln(c);
writeln('Enter  4 number');
readln(d);
if (a=b)and (b=c) and(c=d) then
  begin
       Res:=a+b+c+d;
  end
else
  begin
       writeln('numbers not sames');
  end;
writeln('Res=', Res);
readKey;
end.