uses crt;
var a,b,c,d,n:longword;
begin
clrscr;
write('n=');readln(n);
a:=1;b:=1;c:=1;d:=2;
while c<n do
begin
d:=d+1;
c:=a+b;
a:=b;
b:=c;
end;
write(n,' la phan tu thu ');
if c=n then writeln(d,' trong day fibonacci')
else writeln('0 trong day fibonacci');
readln;
end.
=================================
uses crt;
var n,i:longword;
f:array[1..10000000] of longword;
begin
clrscr;
write('n=');readln(n);
f[1]:=1;f[2]:=1;
for i:=3 to n do f[i]:=f[i-1]+f[i-2];
writeln('Phan tu thu ',n,' trong day fibonacci la ',f[n]);
readln;
end.