i need to make this code run it is written in dart

// Copyright (c) 2012, scribeGriff (Richard Griffith) // https://github.com/scribeGriff/ConvoLab // All rights reserved. Please see the LICENSE.md file. part of convolab; /** * Sorts a list of integers using the Quicksort algorithm. * * This is a classic implementation of the Quicksort divide and * conquer algorithm. * * Example usage: * * List dataList = [10, 9, 8, 7, 6, 5, 4, 3, 2, 1]; * var qsResults = qsort(dataList); * print(qsResults.data); * print(qsResults.value); * * By default, the pivot is computed as the median of 3 elements. The * pivot type can also be specified as the first element, last element, or * two other (differing) types of median 3 choices. For example: * * var qsResults = qsort(dataList, 'first'); * var qsResults = qsort(dataList, 'last'); * var qsResults = qsort(dataList, 'median1'); * var qsResults = qsort(dataList, 'median2'); * * All return the same sorted array but the computational complexity * will be different. * * Returns an object of type QsortResults where the data field is * the sorted list and value is the number of computations performed * to sort the input list. Returns null if input list is null. */ /// The top level function qsort returns the object QsortResults. QsortResults qsort(List unsortedList, [String pivotType = 'median']) { if (unsortedList != null) { QsortResults sortedData = new _QuickSort().sort(unsortedList, pivotType); return new QsortResults(sortedData.data, sortedData.value); } else { return(null); } } /// The private class _QuickSort. class _QuickSort { String pt; int count; _QuickSort() : count = 0; /// Calls recursive method quicksort() and passes array, size and /// pivot method. QsortResults sort(List myArray, String pivotType) { pt = pivotType; quicksort(myArray, 0, myArray.length-1); return new QsortResults(myArray, count); } /// Recursive calls through quicksort keep track of # of comparisons. void quicksort(List inArray, int lo, int hi) { if (hi <= lo) return; count += (hi - lo); int pivot = partition(inArray, lo, hi); quicksort(inArray, lo, pivot-1); // Sort left part a[lo .. i-1]. quicksort(inArray, pivot+1, hi); // Sort right part a[i+1 .. hi]. } int partition(List array, int lo, int hi) { /// Preprocess pivot depending on method /// using a switch list (if 'first' => no need to swap). switch (pt) { case 'last': swap(array, lo, hi); break; case 'median': median3(array, lo, hi); break; case 'median1': median3Alt1(array, lo, hi); break; case 'median2': median3Alt2(array, lo, hi); break; } /// Always set pivot to first element after preprocessing. int pivot = array[lo]; int i = lo+1; int j; /// Scan subarray and sort according to <, > pivot. for (j = lo+1; j <= hi; j++) { if (array[j] < pivot) { swap(array, i, j); i++; } } /// Set up new pivot point. swap(array, lo, i-1); return i-1; } /// Swap two entries in an array: void swap(List array, int i, int j) { int temp = array[i]; array[i] = array[j]; array[j] = temp; } //The following are several median of 3 methods, the //first uses a different number of comparisons than //the second two. void median3(List array, int lo, int hi) { int mid = ((lo + hi) >> 1); int small, median, large; if (array[lo] > array[mid]) { large = lo; small = mid; } else { large = mid; small = lo; } if (array[hi] > array[large]) { median = large; } else if (array[hi] < array[small]) { median = small; } else { median = hi; } swap(array, lo, median); } // The more common approach but one that will provide a different // number of comparisons than the median3(). void median3Alt1(List array, int lo, int hi) { int mid = ((lo + hi) >> 1); if (array[mid].compareTo(array[lo]) < 0 ) { swap(array, lo, mid); } if (array[hi].compareTo(array[lo]) < 0 ) { swap(array,lo, hi); } if (array[hi].compareTo(array[mid]) < 0 ) { swap(array, mid, hi); } swap(array, lo, mid); } // Or if you prefer, you can write Alt1 as follows: void median3Alt2(List array, int lo, int hi) { int mid = ((lo + hi) >> 1); if (array[mid] < array[lo]) swap(array, lo, mid); if (array[hi] < array[lo]) swap(array,lo, hi); if (array[hi] < array[mid]) swap(array, mid, hi); swap(array, mid, lo); } } /** * QsortResults extends standard results class. * * Returns the sorted array and a value for the number of computations * that were performed during the sort. */ class QsortResults extends ConvoLabResults { QsortResults(List data, int value) : super(data, value); }