"Otherwise, let's go back first, shall we? It seems like a game, grab 15 points? But it doesn't seem to be so easy to crack, after all, it's playing with people...... If we delay for a while, we'll be stuck in here. Go back and prepare, study how to play, and come back tomorrow night? Lin Qiuran said.

The man next to him nodded in agreement. This world is so powerful, General Liu, the lord of a city, must be even more powerful, if he is blocked in the house, it is estimated that there will be no future......

Xiao Ling waved his hand: "I'm not in such a hurry." Don't forget, he's rushing this way, and he's also distracted by playing chess, not so fast. He looked at the nine tokens lined up on the jade plate, "Rejoice should have guessed correctly." I kind of know how this thing works. And...... If you do it well, not only will you be able to open the door and enter, but you may also be able to get through the guò thing and block the pursuers outside. ”

Li Dingyi, who was arranging the formation in front of the door and wanted to delay the enemy, didn't know if he should continue to attack.

However, Xiao Ling's friends were bright-eyed. Now that Xiao Ling said that he knew, it was all right. They all cheered up and watched how Xiao Ling played this game.

Xiao Ling sorted out his thoughts a little and decisively started the third round of temptation. Pressed four.

The opposite side pressed five.

Frowning slightly, Xiao Ling continued to go down. After three or four steps and less than ten seconds, it failed, and the jade disk was reset.

The friends looked at Xiao Ling: Didn't you say that it would ≌◇? Why is it still failing?

"After I made the first move, there was only one strategy that could guarantee undefeat, and the other seven would be defeated. So I can only pray that the guy on the other side doesn't have mastered the only one, if he does. Then this door will not be able to open without killing him. Xiao Ling said calmly. This time I pressed six.

Among the friends, the IQ is higher, especially Lin Qiuran who is good at playing games. They all frowned and pondered.

This game seems to be extremely complicated, but if you think about it, it doesn't seem that complicated, and the permutations and combinations, the order, and the sum is 15, which doesn't seem to be much.

But the hard thing is that if you want 15, people will prevent you from getting 15. Add the factor of interference and destruction, and this becomes unpredictable.

Is there only one strategy in the back hand to guarantee undefeated? How do you deduce so many situations? Everyone pondered, but unfortunately it didn't come to fruition.

Xiao Ling pressed six, and the opposite side still pressed five.

Suddenly, Xiao Ling's frown deepened.

Pressing five is the only right strategy. Although they couldn't understand anything else, through Xiao Ling's face, the friends at least realized this.

But why five? Xiao Ling pressed four for the first time and six for the second time. He presses it differently every time, and the opposite side only needs to press five? The friends turned their minds......

Hey, wait, although he pressed it differently every time. Four, five, six, and six, five, four, seem to be equivalent...... If you think so. The situation can be greatly reduced again, it seems only. Eight combinations? It's unimaginably less wow.

159, 168, 249, 258, 267, 348, 357, 456......

However, if you count the order of selection, there are three types of first moves for each one. There are two kinds of responses, and there are many changes at once. And I can't see it at all, why is the backhand undefeated in the fifth hand......

The friends even took out blank rune papers and calculated them intently, but they didn't come to any decent conclusions for a while.

After thinking about it, a new game has begun, and Xiao Ling pressed two this time.

It's changed again...... The friends were speechless.

For those who can barely understand some of them, Longmen Guan Sandao and Zhilin Wuxin can only stare at it, and the bald head is full of fog, the matter is actually very simple, but they have not learned permutations and combinations, and it is really not difficult to understand.

When confused, the opposite side pressed the response, seven.

Sure enough, all possibilities are not blocked! Also, if all possibilities are blocked, there is no need to spend so much time making props and setting up the scene. Xiao Ling looked overjoyed, and immediately pressed five.

The opposite side paused, and picked eight as time was about to end. He also had to press it, otherwise Xiao Ling would have made up fifteen.

One more step, Xiao Ling chose four ......

==========

On the way to the general's mansion at the crossroads, General Liu rushed home with a group of cadres who were roaring angrily.

While hurrying, General Liu stopped from time to time to manipulate the gossip of a jade carving in his hand. The gossip is on the yin and yang Taiji, the dry kan is shocking, and the Xunli Kundui is readily available.

The general who suddenly stopped his feet burst into a shout, and his yellow face turned red: "Damn! Damn it! Damn it! "Lifting the jade gossip, I almost smashed it hard. But in the end, I didn't give up.

hung the jade gossip back on his waist, and roared again and again: "Quick! Fast! Fast! ”

On the way, when they saw soldiers who were busy fighting fires or driving horses, they were all scolded and beckoned to hurry back to the house to rescue the driver, and someone broke into the backyard, and let the people who were greeted continue to greet more people.

For a while, the sound of shouts and shouts resounded in the night sky of Dasanguan. The original sound of fighting the fire and driving the horse was replaced by the sound of returning home to rescue the driver.

==========

After Xiao Ling pressed four, the jade plate no longer changed.

One second, two seconds, until the drop time has passed, there is no change.

In fact, it doesn't make sense to fall on the other side.

Xiao Ling has two, four, and five cards, in addition to the sealed two-five-eight, there are two strategies that can make up for fifteen, two-four-nine, four-five-six. No matter whether the other party fills in nine or six, he can't be stopped.

Let him fall first, as long as the first step of the second hand does not choose five, he will win!

There was no answer on the other side, and Xiao Ling slowly pressed the No. 6 card.

"Boom ......" a sound of machine turning. No, it's not the machine turning, it's vaguely the whole ground turning, a slight tremor. The heavy dà door that leads to the backyard is cast in copper and iron, inlaid with steel nails and engraved with charms, slowly opening open, revealing the inner courtyard shrouded in night.

The friends couldn't help but look at Xiao Ling with admiration.

"Oops, I see!" Suddenly, two exclamations came, one left and one right.

Turning his head, they were Lin Qiuran and Pu Rou.

Lin Qiuran: "Indeed! That's true. As long as you start with two, four, six, and eight, you will lose if you don't choose five in the back hand. ”

Looking at the eyes that focused on him, Lin Qiuran was triumphant and made a few vague gestures. With the mouth shape, let everyone know that he made up a small program to verify Xiao Ling's step algorithm.

That's also a ...... Stupid people have stupid ways, right? Xiao Ling was speechless.

Pu Rou slapped him directly on the back of the head: "This is actually a tic-tac-toe game!" Glancing at Xiao Ling, something that can be understood in such a simple two sentences, this guy has been selling for so long.

Xiao Ling rubbed his nose: "If you don't seize the opportunity to train you, how can you make progress?" ”

Pu Rou: "......"

"Well, tic-tac-toe?" The friends are still puzzled, and the other teammates are also puzzled.

Pu Rou took out a blank piece of talisman paper and drew a tic-tac-toe on it with her mind.

Tic-tac-toe nine grids, a grid fork, a grid circle, alternately, and finally the fork or circle three connected into a line wins.

"Oops, I've played!" The little nun Zhilin said happily. The little monk Wuxin also nodded again and again.

Everyone was speechless, who hasn't played this little game that can be put on a stone for a long time with a casual stroke. But this and that...... Does it matter?

When she was confused, Pu Rou continued to manifest her thoughts, and filled in the numbers on the nine squares of the tic-tac-toe, from left to right, from top to bottom, in three rows, 294, 753, 618.

This is...... Nine-square grid? The game of filling in the numbers to form a total of fifteen is also the basis of Sudoku. No wonder Xiao Ling understood so quickly. Xiao Ling's friends also faintly understood.

Compared with everyone's thoughts, the surprise of Longmen Guan Sandao is deeper: "Carry nine shoes one, three on the left and seven on the right, two or four for the shoulder, six or eight for the foot, with five in the center, Hetu Luoshu?" I see! I see! Playing tic-tac-toe games with Vena nine grids, it turns out that there is still a hidden wonder! ”

Li Dingyi, Yin Sixi, and An ** are all fascinated and grinding......

In fact, this is a question of equivalence, nine number cards pick three to form fifteen, and all its possibilities, permutations and combinations, are on the tic-tac-toe chart. Therefore, how to complete the arrangement can be directly simplified into a tic-tac-toe game.

Whether it is mathematically or computer programming, there is often this situation, in order to solve a problem, the predecessors spent tons of scratch paper, or thousands of lines of code to vomit blood successfully, and another way of thinking, it may be a simple two or three pages of proof, or just ten or twenty lines of code, to solve the problem perfectly.

It seems inconceivable, and its core element is the transformation and substitution of this kind of thinking.

Of course, since people want to say that this is the magic of Hetuluoshu, that is!

At that moment, Xiao Ling was holding a jade plate, taking his friends and watching the Longmen Tour, discussing and discussing, and striding into the backyard of the General's Mansion with his head held high.

Since this is essentially a tic-tac-toe game, then the flop is like a puzzle, and it will connect the residence of a certain three-room lady in a line, so that General Liu can choose one of the three rooms to move in at will.

Not only that, but with the correct arrangement, nine times out of ten, you can directly open the door to the dungeon in the hinterland of Dongshan Mountain.

But until then...... "Who?" Dare to break into the General's Mansion at night! Suddenly, a few coquettish voices came.

At this time, everyone just opened the narrow aisle behind the iron gate, the aisle was not completely enclosed, there were flowers and trees on both sides, and the flowers and trees were blooming, although they could not see clearly, but they could smell the fragrant smell.

I just walked out of the walkway and faced a brightly lit courtyard. From the courtyard, a few slender women with a single knife jumped out, looking dressed as a maid in the backyard or something.

Assembled in a column, the lancet was waved, and it was coquettish to everyone. (To be continued......)