program A;
var x,n,k,e,f:real;
begin
f:=1024*1024*1024 ;
read (n);
e:= 0;
x:=0;
k:=1;
repeat
x:=x+k;
k:=k*n;
e:=e+1;
until (x>=f*2);
writeln (e);
end.