So East =2, West = 1, South =9, North =7 and Middle =8.

5 digits *4 or 5 digits, so East should be less than 3, which means 1 or 2.

Middle × 4 = East, so East is even, and 2 is even.

You can only take 3,8,10,000 digits in the middle, so you can only take 8 in the middle.

East is 2 and middle is 8, so west ×4= north, and north is 1 or 2.

If South ×4 is a single digit, then North is 4 or 8.

If the north is 4 and the north is 48, multiply by 4= 192, it won't work.

If it's North 8 North 88, you can't multiply it by 4=352.

So South ×4 must be a double digit. South > =3

There are two situations:

①2 1 north and south 8×4=8 north and south 12 or 222 north and south 8×4=8 north and south 22

① the first type: 2 1 north and south 8×4=8 north and south 12.

Then the mantissa of 4× North +3 is 1, and North is 2 or 7, respectively.

2 1 south 28×4=82 south 12 or 2 1 south 78*4=87 south 12,

Then the first bit of 4+4×C is 2, so it is not excluded. ......

Or 4+4× South, the first place is 7.

South =8 or 9, substitute 2 1 south 78×4=87 south 12, and south =9, so it is 9. ......

So the five digits are 2 1978.

② The second type: 22 North and South 8×4=8 North and South 22

Then the mantissa of 4× North +3 is 2, which is not excluded.

So it's over, why is there such a abnormal problem in the fourth grade of primary school ... if it weren't for the help of others, I would have died alone.