program kk;
var x,b,c,d,e,k,a,r,n,y,l:real;
begin
writeln('vedite l,b,c,d,k');
readln(l,b,c,d,k);
a:=d+c+b;
r:=exp(-5);
n:=a*r*k;
y:=n-l;
writeln('y=' ,y:7:2);
readln(y);
END.