Difference between revisions of "Fibonacci number"
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</syntaxhighlight> | </syntaxhighlight> | ||
| + | == Iterative way == | ||
| + | This one is preferable. | ||
| + | |||
| + | <syntaxhighlight> | ||
| + | |||
| + | function Fibonacci(n: Integer): Integer; | ||
| + | var | ||
| + | i,u,v,w: Integer; | ||
| + | begin | ||
| + | if n <= 0 then | ||
| + | exit(0); | ||
| + | if n = 1 then | ||
| + | exit(1); | ||
| + | u := 0; | ||
| + | v := 1; | ||
| + | for i := 2 to n do | ||
| + | begin | ||
| + | w := u + v; | ||
| + | u := v; | ||
| + | v := w; | ||
| + | end; | ||
| + | Result := v; | ||
| + | End; | ||
| + | |||
| + | </syntaxhighlight> | ||
== See also == | == See also == | ||
Revision as of 08:05, 23 November 2016
Fibonacci number
The Fibonacci Sequence is the series of numbers:
0, 1, 1, 2, 3, 5, 8, 13, 21, ...
The idea is to add the two last numbers, and thus get the next value.
Recursive way
function FibonacciNumber( n : integer ): integer;
begin
if n > 1 then result := ( FibonacciNumber( n - 1 ) + FibonacciNumber( n - 2 ) )
else
if n = 0 then result := 0
else result := 1;
end;Iterative way
This one is preferable.
function Fibonacci(n: Integer): Integer;
var
i,u,v,w: Integer;
begin
if n <= 0 then
exit(0);
if n = 1 then
exit(1);
u := 0;
v := 1;
for i := 2 to n do
begin
w := u + v;
u := v;
v := w;
end;
Result := v;
End;