uses crt;
const fo='ketqua1.out'
var a:real;
f1:text;
begin
clrscr;
readln(a);
assign(f1,fo); rewrite(f1);
if (a>0) then writeln(f1,sqrt(a):4:2)
else writeln(f1,sqr(a));
close(f1);
readln;
end.
var a:integer;
begin
write('a = '); readln(a);
if a > 0 then write(sqrt(a)) else write(sqr(a));
readln
end.