Generally speaking, if you want to trap a city, the defending side doesn't increase much consumption.
The cost of the encircling side will be several times that of the defending side.
On the one hand, the grain and grass are all around, so there is no need to transport them from other places. On the other hand, the surrounded side is different.
If the same 300000 troops, Zhang Yu's side, but also mobilize hundreds of thousands of people to transport food and grass to them, and these hundreds of thousands of people also have to eat.
In this way, Zhang Yu's side is not about eating 300000 people, but about eating and drinking millions of people.
It's a huge test for Zhang Yu.
Huge consumption, which will make the whole site unbearable.
However, Zhang Yu has no such concerns.
He has a lot of money to use, and food is not a problem.
A large amount of grain and grass is transported here.
Zhang Yu and they began to dig trenches to keep the troops inside.
After several days of digging, a trench more than ten meters wide and two meters deep was dug to encircle the whole city.
"Is Zhang Yu going to trap us?"
There was no war. Cao Cao took people to the city to see.
Cheng Yu shook his head and said, "Zhang Yu is not a man without wisdom. They must have other purposes."
Several counselors and Cao Cao didn't think what Zhang Yu was going to do, but if Zhang Yu didn't attack, they didn't worry.
After a few days in the city, Zhang Yu's army did nothing except defense and training.
It makes them wonder.
Zhang Yu's army, crouching outside the city, finally simply trained there.
Cao Cao went to the city again. Seeing the appearance of the army outside the city, he was always puzzled.
On this day, only Cheng Yu followed him to the city.
"This chapter feather, is not to induce the army of Lu'an to come to support, and then annihilate them." Asked Cao Cao.
Cheng Yu said: "Lord, it's possible, but Zhang Yu has been very urgent in the past two years. Several times, he would rather sacrifice more than speed up the attack. This time, the situation is very unusual."
This time, Zhang Yu changed his tactics and surrounded them in the city.
This may be a long time.
And Zhang Yu, let the soldiers good training, just added a large number of recruits.
And he plans in the big account.
"We can make more comments to make Cao Jun's internal chaos."
"In the absence of Cao Cao, they are expanding again and are in urgent need of talents. They secretly arrange for some people to go there, and their positions can not be promoted. After that, it depends on their abilities."
"If we step up the attack in the north, there may be some internal problems without Cao Cao's instructions."
Zhang Yu is planning and Cao Cao is not. It's a good time to disintegrate them.
Zhang Yu wrote one by one, ready to implement.
It's not useless that he trapped Cao Cao here, on the contrary, it has a great effect.
If Cao Cao is trapped, he can't control the whole Cao group.
Although there are also Cao ang and many of his subordinates, if he is absent for a long time, and rumors abound, there will be internal chaos.
Zhang Yu is to create a lot of internal chaos for the Cao group.
Moreover, with Cao Cao away, many things can't be dealt with in time, and there will certainly be an internal accident at that time.
Soon, a month later, Zhang Yu didn't fight again, but Cao Cao and they were more and more anxious.
At this time, he hasn't received information for a long time, and he doesn't know what's going on here.
At the same time, Cao Jun around is also very anxious.
They wanted to infiltrate, but Zhao Yun sent soldiers to cover all the surrounding areas for ten li, and then searched intensively for 30 Li to prevent the enemy's scouts from entering.
In this way, Cao Cao completely lost contact with the outside world.
Cao Cao is calm on this side, but not on the outside.
Cao Cao was surrounded inside, and other Cao troops were very nervous. Cao Cao lost contact with his general for about a month, which made them very nervous.
I'm very nervous. I don't know what to do.
Cao Jun around restless, but dare not easily send troops, afraid of Zhang Yu's trap.
Aware of this, Cao Cao said, "we have been besieged for a month, and we don't know what's going on here. It's very bad for us. I'm afraid some troops will be fooled and rush to rescue us."
Cao Cao asked Ji to see if there was any way.
As a result, no one could help.
"Get out of here?"
Obviously not.
Zhang Yu built a solid defense line outside, and then dug a ditch. They couldn't jump through the ditch.
In this way, Cao Cao and they had no choice.
However, Zhang Yu did want to bring out the troops of other cities, but this was not the main purpose.
For a month, Zhang Yu didn't do anything.
The rumor mongers are ready to start any time.
In addition, Zhang Liao's attack was also smooth.
Everything is developing in the direction of Zhang Yu's idea.
After a few days, Zhang Yu still didn't do anything.
A lot of supplies came in.
Zhang Yu has been planning for a long time in the big account. He came out to have a look this day.
"Ha ha, there are fairs here."
Zhang Yu made an inspection, but some people came here to sell things.
Of course, this is also allowed by Zhang Yu. All the people who can come here are selected from Hefei city.
However, they can only be in the periphery, because Zhang Yu asked them to help transport grain and grass, and some people brought some things to sell.
"Well, it's good. There's fruit to eat."
Zhang Yu bought some fruit in a small market.
"General, if you like, eat more. No money. " Said the fellow seller.
Zhang Yu took another orange to eat.
"Money must be given, or no one dares to eat."
The common people also laughed, they dare to come here to sell things, that is to know that the army here will give money.
Other places are afraid of the army, but they are not.
Zhang Yu strolled around and saw the people helping to transport grain and grass, as well as a lot of firewood.
If the army wants to cook, it needs to burn a fire and let the people transport.
Zhang Yu felt that these people must have spies from the enemy, who happened to spread the news.
Zhang Yu deliberately buys food from a small vendor.
"Brother, how's business selling chaos here?"
It was an old man who sold chaos. He laughed and said, "ha ha, it's all the help. Business is good."
Zhang Yu took a few mouthfuls and then boasted that it tasted good.
The old man saw that Zhang Yu was easy to talk. At this time, he was just idle, so he asked, "general, how long will this battle last?"
"I don't know. Cao Cao is very ill. If he dies, it will be easier to fight. There won't be so many people dying in vain." Zhang Yu said after another bite.
The old man said, "yes, what a good baby. It's a pity to die on the battlefield."
Zhang Yu deliberately revealed some less important information.
Zhang Yu turned around and ordered some troops to train outside.