桶排序

public static void main(String[] args) {
    int[] arr = {5, 2, 4, 1};
    // 初始化桶，对应值的位置增加
    int[] tong = new int[6];
    for (int i = 0; i < arr.length; i++) {
        tong[arr[i]]++;
    }
    // 遍历所有的桶
    for (int i = 0; i < 6; i++) {
        for (int j = 1; j <= tong[i]; j++) {
            System.out.println(i);
        }
    }
}