Java 理解基数排序算法

我试图理解这个基数排序算法是如何工作的。我不熟悉算法和比特，所以这对我来说并不容易。到目前为止，我已经在我的代码中添加了这些注释，以使代码更容易理解。我不确定我是否正确理解了这个概念，因此如果有人看到我的评论有任何问题/我没有正确理解的内容，请帮助我：）

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还有谁能给我解释一下这行代码：mask=1我会按相反的顺序回答你的问题

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mask=1等等……你以前没问过这个问题吗？

public static ArrayList<Integer> RadixSort(ArrayList<Integer> a)
    //This method implements the radix sort algorithm, taking an integer array as an input
    {
        ArrayList<Integer> array = CopyArray(a);
        //Created a new integer array called 'array' and set it to equal the array inputed to the method
        //This was done by copying the array entered to the method through the CopyArray method, then setting the results of the method to the new empty array

        Integer[] zerobucket = new Integer[a.size()];
        Integer[] onebucket = new Integer[a.size()];
        //Created two more integer arrays to act as buckets for the binary values
        //'zerobucket' will hold array elements where the ith bit is equal to 0
        //'onebucket' will hold array elements where the ith bit is equal to 1

        int i, bit;
        //Created two integer variables i & bit, these will be used within the for loops below
        //Both i & bit will be incremented to run the radix sort for every bit of the binary value, for every element in the array

        Integer element, mask;
        //Created an integer object called element, this will be used to retrieve the ith element of the unsorted array
        //Created an integer object called mask, this will be used to compare the bit values of each element

        for(bit=0; bit<8; ++bit)
        //Created a for loop to run for every bit of the binary value e.g.01000000
        //Change from 8 to 32 for whole integers - will run 4 times slower
        {
            int zcount = 0;
            int ocount = 0;
            //Created two integer variables to allow the 'zerobucket' and 'onebucket' arrays to be increment within the for loop below

            for(i=0; i<array.size(); ++i)
            //Created a nested for loop to run for every element of the unsorted array
            //This allows every bit for every binary value in the array
            {
                element = array.get(i);
                //Set the variable 'element' to equal the ith element in the array
                mask = 1 << bit;

                if ((element & mask) == 0)
                //If the selected bit of the binary value is equal to 0, run this code
                {
                    zerobucket[zcount++] = array.get(i);
                    //Set the next element of the 'zerobucket' array to equal the ith element of the unsorted array
                }
                else
                //Else if the selected but of the binary value is not equal to 0, run this code
                {
                    onebucket[ocount++] = array.get(i);
                    //Set the next element of the 'onebucket' array to equal the ith element of the unsorted array
                }
            }

            for(i=0; i<ocount; ++i)
            //Created a for loop to run for every element within the 'onebucket' array
            {
                array.set(i,onebucket[i]);
                //Appended the ith element of the 'onebucket' array to the ith position in the unsorted array
            }

            for(i=0; i<zcount; ++i)
            //Created a for loop to run for every element within the 'zerobucket' array
            {
                array.set(i+ocount,zerobucket[i]);
                //Appended the ith element of the 'zerobucket' array to the ith position in the unsorted array
            }
        }
        return(array);
        //Returned the sorted array to the method
    }

array = copy (a)
for every bit position from 0 to radix // radix is 8
    for each item in array
        if bit at bit position in item is 0
            put item in zeroes bucket
        else
            put item in ones bucket
    array = ordered concatenation of ones bucket and zeroes bucket
return array