52 lines
1.4 KiB
JavaScript
52 lines
1.4 KiB
JavaScript
|
(function (exports) {
|
||
|
|
'use strict';
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Sorts strings lexicographically.<br><br>
|
||
|
|
* Time complexity: O(N*M) for N keys which have M or fewer digits.
|
||
|
|
*
|
||
|
|
* @example
|
||
|
|
*
|
||
|
|
* var sort = require('../src/sorting/lsd').lsd;
|
||
|
|
* // [ 'aab', 'aaa', 'acc', 'bbb', 'bcc' ]
|
||
|
|
* console.log(sort(['aab', 'bbb', 'aaa', 'acc', 'bcc']));
|
||
|
|
*
|
||
|
|
* @public
|
||
|
|
* @module sorting/lsd
|
||
|
|
* @param {Array} arr Array which should be sorted.
|
||
|
|
* @param {Number} letterIdx Optional. Index to start sorting from.
|
||
|
|
* @return {Array} Sorted array.
|
||
|
|
*/
|
||
|
|
function lsd(arr, letterIdx) {
|
||
|
|
var temp;
|
||
|
|
var count;
|
||
|
|
letterIdx = letterIdx || 1;
|
||
|
|
for (var i = letterIdx - 1; i >= 0; i -= 1) {
|
||
|
|
count = [];
|
||
|
|
temp = [];
|
||
|
|
for (var j = 0; j < arr.length; j += 1) {
|
||
|
|
var charCode = arr[j].charCodeAt(i);
|
||
|
|
var old = count[charCode + 1] || 0;
|
||
|
|
count[charCode + 1] = old + 1;
|
||
|
|
}
|
||
|
|
for (var c = 0; c < count.length - 1; c += 1) {
|
||
|
|
count[c] = count[c] || 0;
|
||
|
|
count[c + 1] = count[c + 1] || 0;
|
||
|
|
count[c + 1] += count[c];
|
||
|
|
}
|
||
|
|
for (j = 0; j < arr.length; j += 1) {
|
||
|
|
var code = arr[j].charCodeAt(i);
|
||
|
|
temp[count[code]] = arr[j];
|
||
|
|
count[code] += 1;
|
||
|
|
}
|
||
|
|
for (j = 0; j < arr.length; j += 1) {
|
||
|
|
arr[j] = temp[j];
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return arr;
|
||
|
|
}
|
||
|
|
|
||
|
|
exports.lsd = lsd;
|
||
|
|
|
||
|
|
})(typeof window === 'undefined' ? module.exports : window);
|