uses crt;
const fi='input.txt'
fo='output.txt'
var f1,f2:text;
a,b:integer;
begin
assign(f1,fi); reset(f1);
assign(f2,fo); rewrite(f2);
readln(f1,a,b);
if (a=0) and (b=0) then writeln(f2,'Phuong trinh co vo so nghiem');
if (a<>0) then writeln(f2,-b/a:4:2);
if (a=0) and (b<>0) then writeln(f2,'Phuong trinh vo nghiem');
close(f1);
close(f2);
end.