看下面的算式：
□□ x □□ = □□ x □□□
它表示：两个两位数相乘等于一个两位数乘以一个三位数。
如果没有限定条件，这样的例子很多。
但目前的限定是：这9个方块，表示1~9的9个数字，不包含0。
该算式中1至9的每个数字出现且只出现一次！
比如：
46 x 79 = 23 x 158
54 x 69 = 27 x 138
54 x 93 = 27 x 186
.....
请编程，输出所有可能的情况！
import java.util.ArrayList;
import java.util.List;
public class ChessNum {
static List<Integer> list;
static int one,two,three,four;
static int a,b,c,d,e,f,g,h,z;
public static void main(String[] args) {
list = new ArrayList<Integer>();
getList();
for (int i = 1; i <= 9; i++) {
a = list.get(i);
list.set(i, 0);
for (int j = 1; j <= 9; j++) {
if (list.get(j) != 0) {
b = list.get(j);
list.set(j, 0);
for (int k = 1; k <= 9; k++) {
if (list.get(k) != 0) {
c = list.get(k);
list.set(k, 0);
for (int l = 1; l <= 9; l++) {
if (list.get(l) != 0) {
d = list.get(l);
list.set(l, 0);
for (int m = 1; m <= 9; m++) {
if (list.get(m) != 0) {
e = list.get(m);
list.set(m, 0);
for (int n = 1; n <= 9; n++) {
if (list.get(n) != 0) {
f = list.get(n);
list.set(n, 0);
for (int o = 1; o <= 9; o++) {
if (list.get(o) != 0) {
g = list.get(o);
list.set(o, 0);
for (int p = 1; p <= 9; p++) {
if (list.get(p) != 0) {
h = list.get(p);
list.set(p,
0);
for (int q = 1; q <= 9; q++) {
if (list.get(q) != 0) {
z = list.get(q);
list.set(
q,
0);
if(builtOne(a, b)*builtTwo(c,d)==builtThree(e, f)*builtFour(g, h, z))
{
System.out.println(builtOne(a, b)+"x"+builtTwo(c,d)+"="+builtThree(e, f)+"x"+builtFour(g, h, z));
}
}
}
addList(list);
list.set(i,0);
list.set(j,0);
list.set(k,0);
list.set(l,0);
list.set(m,0);
list.set(n,0);
list.set(0,0);
}
}
addList(list);
list.set(i,0);
list.set(j,0);
list.set(k,0);
list.set(l,0);
list.set(m,0);
list.set(n,0);
}
}
addList(list);
list.set(i,0);
list.set(j,0);
list.set(k,0);
list.set(l,0);
list.set(m,0);
}
}
addList(list);
list.set(i,0);
list.set(j,0);
list.set(k,0);
list.set(l,0);
}
}
addList(list);
list.set(i,0);
list.set(j,0);
list.set(k,0);
}
}
addList(list);
list.set(i,0);
list.set(j,0);
}
}
addList(list);
list.set(i,0);
}
}
addList(list);
}
}
public static void addList(List<Integer> list)
{
for (int r = 1; r <= 9; r++) {
list.set(r, r);
}
}
private static void getList() {
for(int i=0;i<=9;i++)
{
list.add(i,i);
}
}
public static int builtOne(int a,int b)
{
return a*10+b;
}
public static int builtTwo(int a,int b)
{
return a*10+b;
}
public static int builtThree(int a,int b)
{
return a*10+b;
}
public static int builtFour(int a,int b,int c)
{
return a*100+b*10+c;
}
}
结果：存在重复，这个暴力运算实在是让人头晕
46x79=23x158
54x69=27x138
54x93=27x186
56x73=14x292
58x67=29x134
58x69=23x174
58x73=29x146
58x96=32x174
63x74=18x259
64x79=32x158
67x58=29x134
69x54=27x138
69x58=23x174
73x56=14x292
73x58=29x146
73x96=12x584
74x63=18x259
76x98=14x532
79x46=23x158
79x64=32x158
79x84=12x553
84x79=12x553
93x54=27x186
96x58=32x174
96x73=12x584
98x76=14x532