You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

56 lines
1.6 KiB
JavaScript

(function (exports) {
'use strict';
var variationsWithRepetion = (function () {
var res;
function variations(arr, k, index, current) {
if (k === index) {
return res.push(current.slice());
}
for (var i = 0; i < arr.length; i += 1) {
current[index] = arr[i];
variations(arr, k, index + 1, current);
}
}
/**
* Finds all the variations with repetition of given array.<br><br>
* Variations with repetition is the number of ways to sample k elements
* from a set of elements (which may be repeated).
*
* @example
* var variations = require('path-to-algorithms/src/combinatorics/' +
* 'variations-repetition').variationsWithRepetion;
* var result = variations(['apple', 'orange', 'pear'], 2);
*
* // [['apple', 'apple'],
* // ['apple', 'orange'],
* // ['apple', 'pear'],
* // ['orange', 'apple'],
* // ['orange', 'orange'],
* // ['orange', 'pear'],
* // ['pear', 'apple'],
* // ['pear', 'orange'],
* // ['pear', 'pear']]
* console.log(result);
*
* @module combinatorics/variations-repetition
* @public
* @param arr {Array} Set of items.
* @param k {Number} Size of each combination.
* @return {Array} Returns all combinations.
*/
return function (arr, k) {
res = [];
variations(arr, k, 0, []);
var temp = res;
res = undefined;
return temp;
};
}());
exports.variationsWithRepetion = variationsWithRepetion;
}((typeof window === 'undefined') ? module.exports : window));