数字魔方

看到一个有趣的数字魔方，就像下面这样：

1   36  35  34  33  32   31  30  29  28
2   37  64  63  62  61   60  59  58  27
3   38  65  84  83  82   81  80  57  26
4   39  66  85  96  95   94  79  56  25
5   40  67  86  97  100  93  78  55  24
6   41  68  87  98  99   92  77  54  23
7   42  69  88  89  90   91  76  53  22
8   43  70  71  72  73   74  75  52  21
9   44  45  46  47  48   49  50  51  20
10  11  12  13  14  15   16  17  18  19

有高人用SQL把它给显示出来了，还用各种算法写出各种版本，用SQL我确实是写不出来，不过想了想用Java实现了一个。

ArrayUtil.java:用来格式化输出的。

import java.util.Arrays;public class ArrayUtils {enum ALIGN{LEFT,MIDDLE,RIGTH};public <T> String formatTable(T[][] table){StringBuilder builder = new StringBuilder();int[] colWidths = getColWidth(table);for(int i = 0; i < table.length; i++){for(int j = 0; j < table[i].length - 1; j++){builder.append(formatString(table[i][j].toString(), colWidths[j], ALIGN.LEFT));builder.append(" ");}builder.append(formatString(table[i][table[i].length - 1].toString(), colWidths[table[i].length - 1], ALIGN.LEFT));builder.append("/n");}return builder.toString();}private String formatString(String string, int width, ALIGN align) {int len = string.length();int leftBlanks;int rightBlanks;switch(align){case LEFT:default:leftBlanks = 0;rightBlanks = width - len;break;case MIDDLE:leftBlanks = (width - len) / 2;rightBlanks = width - len - leftBlanks;break;case RIGTH:leftBlanks = width - len;rightBlanks = 0;break;}StringBuilder builder = new StringBuilder();for(int i = 0; i < leftBlanks; i++){builder.append(" ");}builder.append(string);for(int i = 0; i < rightBlanks; i++){builder.append(" ");}return builder.toString();}private <T> int[] getColWidth(T[][] table){int[] width = new int[table[0].length];Arrays.fill(width, 0);for(int i = 0; i < table.length; i++){for(int j = 0; j < table[i].length; j++){if(table[i][j].toString().length() > width[j]){width[j] = table[i][j].toString().length();}}}return width;}/** * @param args */public static void main(String[] args) {String[][] arr = new String[][]{{"a", "bac","ef"},{"a","sswwf","asef"},{"eds","as","wxsa"},{"w222","22","yy"}};System.out.println(Arrays.deepToString(arr));System.out.println(new ArrayUtils().formatTable(arr));}}
MagicArray.java:这个实现了魔方的算法

import java.util.Arrays;public class MagicArray {public Integer[][] getMagic(int n) {Integer[][] ret = new Integer[n][n];int value = 1;int max = n;int min = 0;while (true) {for (int i = min; i < max; i++) {// (1,1)->(n,1)ret[i][n - max] = value++;}for (int i = min + 1; i < max; i++) {//(n,1)->(n,n)ret[max - 1][i] = value++;}for (int i = max - 2; i > min; i--) {//(n,n)->(1,n)ret[i][max - 1] = value++;}for (int i = max - 1; i > min; i--) {//(1,n)->(1,1)ret[min][i] = value++;}min++;max--;if (min >= max)//overbreak;}return ret;}/** * @param args */public static void main(String[] args) {MagicArray magic = new MagicArray();Integer[][] arr = magic.getMagic(10);// System.out.println(Arrays.deepToString(arr));ArrayUtils util = new ArrayUtils();System.out.println(util.formatTable(arr));}}