The Fibonacci sequence is a sequence of numbers, where every number in the sequence is the sum of the two numbers preceding it. The first two numbers in the sequence are both 1. Here are the first few terms:
1 1 2 3 5 8 13 21 34 55 89 ...
Write the shortest code that either:
Generates the Fibonacci sequence without end.
Given
ncalculates thenth term of the sequence. (Either 1 or zero indexed)
You may use standard forms of input and output.
(I gave both options in case one is easier to do in your chosen language than the other.)
For the function that takes an n, a reasonably large return value (the largest Fibonacci number that fits your computer's normal word size, at a minimum) has to be supported.
Leaderboard
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// It will be like https://XYZ.stackexchange.com/questions/QUESTION_ID/... on any question page
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var OVERRIDE_USER = 3; // This should be the user ID of the challenge author.
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function answersUrl(index) {
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url: answersUrl(answer_page++),
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data.items.forEach(function(a) {
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url: commentUrl(comment_page++, answer_ids),
method: "get",
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if (data.has_more) getComments();
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getAnswers();
var SCORE_REG = /<h\d>\s*([^\n,<]*(?:<(?:[^\n>]*>[^\n<]*<\/[^\n>]*>)[^\n,<]*)*),.*?(\d+)(?=[^\n\d<>]*(?:<(?:s>[^\n<>]*<\/s>|[^\n<>]+>)[^\n\d<>]*)*<\/h\d>)/;
var OVERRIDE_REG = /^Override\s*header:\s*/i;
function getAuthorName(a) {
return a.owner.display_name;
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function process() {
var valid = [];
answers.forEach(function(a) {
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valid.sort(function (a, b) {
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return aB - bB
});
var languages = {};
var place = 1;
var lastSize = null;
var lastPlace = 1;
valid.forEach(function (a) {
if (a.size != lastSize)
lastPlace = place;
lastSize = a.size;
++place;
var answer = jQuery("#answer-template").html();
answer = answer.replace("{{PLACE}}", lastPlace + ".")
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answer = jQuery(answer);
jQuery("#answers").append(answer);
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{
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var lang = langs[i];
language = language.replace("{{LANGUAGE}}", lang.lang)
.replace("{{NAME}}", lang.user)
.replace("{{SIZE}}", lang.size)
.replace("{{LINK}}", lang.link);
language = jQuery(language);
jQuery("#languages").append(language);
}
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text-align: left !important;
display: block !important;
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padding: 10px;
width: 290px;
float: left;
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padding: 10px;
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float: left;
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font-weight: bold;
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padding: 5px;
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<link rel="stylesheet" type="text/css" href="https://cdn.sstatic.net/Sites/codegolf/all.css?v=ffb5d0584c5f">
<div id="language-list">
<h2>Shortest Solution by Language</h2>
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<h2>Leaderboard</h2>
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<table style="display: none">
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<tr><td>{{PLACE}}</td><td>{{NAME}}</td><td>{{LANGUAGE}}</td><td>{{SIZE}}</td><td><a href="{{LINK}}">Link</a></td></tr>
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<table style="display: none">
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<tr><td>{{LANGUAGE}}</td><td>{{NAME}}</td><td>{{SIZE}}</td><td><a href="{{LINK}}">Link</a></td></tr>
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