点击開始，查看netManager，点击面板的监听程序，默认仅仅有地址1且标记着localhost。新建一个地址，输入本机IP，又一次开启监听程序就可以
△△△ * △△ = △△△△
某3位数乘以2位数，结果为4位数
要求：在9个△所代表的数字中，1~9的数字恰好每一个出现1次。
public class Pruning {
public static void main(String[] args) {
int n1, n2, n3, n4, n5, n6, n7, n8, n9;
for (int i = 123; i <= 987; i++) {
n1 = i / 100;
n2 = i / 10 % 10;
n3 = i % 10;
if (n1 == 0 || n2 == 0 || n3 == 0 ) {
continue;
}
if( n1 == n2 || n1 == n3
|| n2 == n3){
continue;
}
for (int j = 12; j <= 98; j++) {
n4 = j / 10;
n5 = j % 10;
if (n4 == 0 || n5 == 0 ) {
continue;
}
if( n4 == n5 || n4 == n1 || n4 == n2
|| n4 == n3 || n5 == n1 || n5 == n2 || n5 == n3){
continue;
}
for (int k = 1234; k <= 9876; k++) {
n6 = k / 1000;
n7 = k / 100 % 10;
n8 = k / 10 % 10;
n9 = k % 10;
if((n3*n5)%10!=n9){
continue;
}
if (n6 == 0 || n7 == 0 || n8 == 0 || n9 == 0 || n6 == n7
|| n6 == n8 || n6 == n9 || n7 == n8 || n7 == n9
|| n8 == n9 || n6 == n1 || n6 == n2 || n6 == n3
|| n6 == n4 || n6 == n5 || n7 == n1 || n7 == n2
|| n7 == n3 || n7 == n4 || n7 == n5 || n8 == n1
|| n8 == n2 || n8 == n3 || n8 == n4 || n8 == n5
|| n9 == n1 || n9 == n2 || n9 == n3 || n9 == n4
|| n9 == n5) {
continue;
}
if (i * j == k) {
System.out.println(i + " " + j + " " + k);
}
}
}
}
}
}