17 lines
322 B
ObjectPascal

var
n:longint;
function fbi(i:longint):longint;
begin
if i=1 then exit(0)
else if i=2 then exit(1)
else exit(fbi(i-1)+fbi(i-2));
end;
begin
assign(input,'fbi.in'); reset(input);
assign(output,'fbi.out'); rewrite(output);
readln(n);
writeln(fbi(n));
close(input);
close(output);
end.