题解 | #排序（基数排序）#

import java.io.*;
import java.util.Arrays;

public class Main {
    public static int n;
    public static final int MAX = 501;
    public static int[] arr = new int[MAX];
    //表示是多少进制
    public static int base = 10;
    //词频数组，用于记录数字的每位出现的频率
    public static int[] cnts = new int[base];
    public static int[] help = new int[MAX];

    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        StreamTokenizer in = new StreamTokenizer(br);
        PrintWriter out = new PrintWriter(new OutputStreamWriter(System.out));
        while (in.nextToken() != in.TT_EOF) {
            n = (int) in.nval;
            for (int i = 0; i < n; i++) {
                in.nextToken();
                arr[i] = (int) in.nval;
            }
            sort();
            for (int i = 0; i < n; i++) {
                out.print(arr[i] + " ");
            }
            out.println();
        }
        out.flush();
        out.close();
    }

    //计算出一个正整数有几位
    public static int bits(int num) {
        int ans = 0;
        while (num != 0) {
            ans++;
            num /= base;
        }
        return ans;
    }


    public static void sort() {
        //如果数组中有负数
        int min = arr[0];
        for (int i = 0; i < n; i++) {
            min = Math.min(min, arr[i]);
        }
        int max = arr[0] - min;
        for (int i = 0; i < n; i++) {
            arr[i] = arr[i] - min;
            max = Math.max(max, arr[i]);
        }
        int bits = bits(max);
        radixSort(bits);
        for (int i = 0; i < n; i++) {
            arr[i] = arr[i] + min;
        }
        
    }

    public static void radixSort(int bits) {
        for (int offset = 1; bits > 0; offset *= base, bits--) {
            Arrays.fill(cnts, 0);
            for (int i = 0; i < n; i++) {
                cnts[(arr[i] / offset) % base]++;
            }
            for (int i = 1; i < base; i++) {
                cnts[i] = cnts[i - 1] + cnts[i];
            }
            for (int i = n - 1; i >= 0; i--) {
                help[--cnts[(arr[i] / offset) % base]] = arr[i];
            }
            for (int i = 0; i < n; i++) {
                arr[i] = help[i];
            }
        }
    }
}