Here a more mathematical way of seeing it, though not really complicated. IMO much clearer as informal ones: The question is, how many times can you divide N by 2 until you have 1? This is essentially saying, do a binary search (half the elements) until you found it. In a formula this would be … Read more
I cannot understand how to identify a function with a log time. The most common attributes of logarithmic running-time function are that: the choice of the next element on which to perform some action is one of several possibilities, and only one will need to be chosen. or the elements on which the action is … Read more
Modern browsers have Array#includes, which does exactly that and is widely supported by everyone except IE: Run code snippet You can also use Array#indexOf, which is less direct, but doesn’t require polyfills for outdated browsers. Run code snippet Many frameworks also offer similar methods: jQuery: $.inArray(value, array, [fromIndex]) Underscore.js: _.contains(array, value) (also aliased as _.include and _.includes) Dojo Toolkit: dojo.indexOf(array, value, [fromIndex, findLast]) Prototype: array.indexOf(value) MooTools: array.indexOf(value) MochiKit: findValue(array, value) MS … Read more