Interpretation of Han Xin's divination strategy

Han Xin dark soldier song formula:

Three people walked with each other for seventy days, and five counted twenty-one plum blossoms, and the seven sons reunited exactly half a month. When they arrived at 105, they learned.

Han Xin dark point soldier, Han Xin is not one, two, three, but, let the team lined up:

First of all, three people in a row, remember the extra number;

Let five people queue up again and remember the extra number;

Make another row of seven people, and remember the extra number.

Add up the above three redundant people. He knows how many people there are.

Calculation:

For example, the remainder of three lines, the remainder is two. Then: 2*70= 140 (the remainder cannot exceed 2)

The remainder of five queues, for example, if the remainder is four, then: 4*2 1=84 (the remainder cannot exceed four).

The remainder of seven queues, for example, the remainder is six, then: 6* 15=90 (the remainder cannot exceed six).

The above results add up: 140+84+90=3 14.

If it is estimated that there are no more than 300 people, it is: 3 14— 105=209.

If there are no more than 200 people, and then subtract 105, then: 209-105 =104.

All right. Yes 104 person.

Note: In addition to the above calculation, we need to make an estimate. Then compare and calculate approximate numbers.