# The Knights and the Hounds

(With thanks and congratulations to Lee Leon)

We rejoin our heroes several days after the events of The Knights' Gift, at the head of a pack of enormous staghounds, 1000 strong. Such a pack had never before been seen, and the barking and howling carried for many leagues.

It was a mighty pack, full of hounds of every color and pattern – 540 were solid, 2 for every hound that was mottled. 330 were brown but not spotted, and 120 were spotted but not brown.

Among the white dogs, twice as many were solid as were mottled, and half again were mottled as were spotted. And among the 380 grey animals, half as many were spotted as were mottled.

Said one knight, “Did you really have to ask for 1000 enormous staghounds? We shall surely go broke feeding them, let alone finding a suitable place for them to live!

“Fear not!”, the other replied. “For I am in possession of a large quantity of land. We can divide it into 100 plots – 10 on each side – and there will be ample space for 10 staghounds per plot, even enormous as they may be. We shall divide the 100 plots into 9 rectangular pens, so that the animals may be sorted according to color and pattern.”

“Well, enough space is one thing, but how shall we arrange it? After all, not all the hounds get along – we must avoid letting any of the spotted dogs share fences with any of the mottled dogs. Well… except for the white spotted dogs, which seem to get along with the mottled dogs just fine.”

“Yes, that’s an excellent plan! And we must keep their special needs in mind, as well. The solid brown hounds should have at least 2 fence sections along the Southern edge, so that they can feel the sun on their fur, and the solid white hounds need at least 2 fence sections along the Eastern edge, so that they may feel the wind at their backs. And lastly, the grey solid and grey mottled animals are very friendly with each other and should share at least one fence section.”

“Very well, but with so many constraints, are you sure there’s a way to arrange them all?”

The knights stopped for a few moments, considering, then one opened a piece of parchment and began to sketch…

Hint #1

Solid brown has exactly 4 fence sections along the southern border. Solid white has exactly 2 fence sections along the eastern border. Grey solid/grey mottled share exactly 6 fence sections.

With the help of Hint 1, here's the full answer.

First, the number of each kind of hound.

Hound table  | brown | white | grey | total solid | 280 | 120 | 140 | 540 mottled | 50 | 60 | 160 | 270 spotted | 70 | 40 | 80 | 190 total | 400 | 220 | 380 | 1000 
We start by finding pattern totals. solid = 540, mottled = solid/2 and spotted is what's left. 120 are spotted not brown so there are 190-120 = 70 that are spotted and brown. There are 70+330 = 400 total brown, and since grey = 380, white = 220. Then (white solid) = 2*(white mottled), (white mottled) = 1.5*(white spotted), so white = 220 = 2*(white mottled) + (white mottled) + 2/3*(white mottled) = 11/3*(white mottled) therefore, white mottled = 60. Following white spotted = 40 and white solid = 120. grey spotted = 190-70-40 = 80, then doubled for grey mottled = 160. The rest can be figured out be subtracting the other two from the total.

Possible pen dimensions

Now that we have the totals we can find all the possible pen dimensions. The longest side must be 10 or lower to fit on the land. Here are the possibilities.

solid brown = 4x7
solid white = 2x6, 3x4
solid grey = 2x7
mottled brown = 1x5
mottled white = 1x6, 2x3
mottled grey = 2x8, 4x4
spotted brown = 1x7
spotted white = 1x4, 2x2
spotted grey = 1x8, 2x4

Taking Hint 1 into account we can further reduce the following:

solid white = 2x6
mottled grey = 2x8

Pen arrangement

I found the arrangement with simple trial and error and a few good guesses.

solid brown = A
solid white = B
solid grey = C
mottled brown = D
mottled white = E
mottled grey = F
spotted brown = G
spotted white = H
spotted grey = I
 HHIIIIIIII HHCCBBBBBB FFCCBBBBBB FFCCDAAAAG FFCCDAAAAG FFCCDAAAAG FFCCDAAAAG FFCCDAAAAG FFEEEAAAAG FFEEEAAAAG 

• Nicely done! I'm glad someone finally finished this! – Selvek Aug 17 '18 at 18:33

Partial answer with about the numbers of the Hounds, since the other answers are incorrect in their reading of the text (in my opinion)

This assumes that there are only grey, brown and white dogs and only solid, mottled and spotted dogs, as no others are mentioned in the question

basic facts:  n = 1000 white + grey + brown = n spotted + mottled + solid = n 

patterns:

1. solid = 540 2. mottled = solid/2 = 270

colours:

3. White = 380

combinations:

4. brown and not spotted: 330 5. spotted and not brown: 120 6. white and solid = 2 * white and mottled 7. white and mottled = 1.5 * white and spotted 8. grey and spotted = 1/2 grey and mottled

deductions:

spotted = 1000 - mottled - solid = 190 now we have all the numbers of the patterns. from this and 5 we get brown and spotted = 70 so we have brown = brown and spotted + brown and not spotted = 400 so far we have solid | mottled | spotted 540 | 270 | 190 brown | 400 | A | B | 70 grey | 380 | C | 2*D | D white | 220 | 3*E | 1.5*E | E white can be solved immediately: white | 220 = 3*E + 1.5*E + E = 5.5 E => E = 40 so white becomes 120 + 60 + 40 with this, spotted can be solved and grey and spotted is 80 from this we get grey and mottled = 160 we can now solve the whole grid nicely: solid | mottled | spotted 540 | 270 | 190 brown | 400 | 280 | 50 | 70 grey | 380 | 140 | 160 | 80 white | 220 | 120 | 60 | 40 

I don't have time right now to do the next part but I might try it in a few hours if it is still unsolved.

EDIT: Okay I am at least starting now.

Assumption: 100 plots laid out in a square to be divided into 9 rectangles with the following size and possible layouts:

brown and solid: 28 : 4 x 7 brown and mottled: 5 : 1 x 5 brown and spotted: 7 : 1 x 7 grey and solid: 14 : 2 x 7 grey and mottled: 16 : 4 x 4, 2 x 8 grey and spotted: 8 : 2 x 4, 1 x 8 white and solid: 12 : 2 x 6, 3 x 4 white and mottled: 6 : 2 x 3, 1 x 6 white and spotted: 4 : 2 x 2, 1 x 4 100

These have the following restrictions:

spotted cannot border mottled except for white spotted solid brown need 2 section of the southern border solid white need 2 sections of the eastern border grey solid and mottled need to share at least one section border hint 1: solid Brown has exaclt 4 sections on the southern border solid white has exactly 2 sections on the eastern border solid and mottled grey share exactly 6 fence sections

we can thus eliminate certain shapes:

brown and solid: 28 : 4 x 7 brown and mottled: 5 : 1 x 5 brown and spotted: 7 : 1 x 7 grey and solid: 14 : 2 x 7 grey and mottled: 16 : 2 x 8 grey and spotted: 8 : 2 x 4, 1 x 8 white and solid: 12 : 2 x 6 white and mottled: 6 : 2 x 3, 1 x 6 white and spotted: 4 : 2 x 2, 1 x 4 100

Observations:

white solid needs to be in the north eastern corner or one line below that, there is no ohter way brown solid needs to be below white solid in the south eastern corner otherwise there is no way to arange grey solid and mottled without leaving gaps solid grey and mottled grey are next to each other and both aligned vertically either grey solid or grey mottled is immediatly touching brown solid if grey Mottled is on the western side of the pair then there seems to be no way of arranging the spotted dogs without a conflict but if they are on the eastern side then there are two areas of height 1 and width 4

• So far so good! – Selvek Apr 6 '18 at 15:25
• @Selvek I'm having quite a hard time continuing as i don't see a way to split the layout problem into meaningfull subproblems. i might have another go at it tomorrow. The main problem is that i don't know the correct shape for half of the blocks. – n0m4d3 Apr 6 '18 at 17:18
• That's fair. If there's no progress in a day or so I'll start adding more hints. It's tough to find the right difficulty balance (especially since many of the people here are waaay better at puzzles than I am!) – Selvek Apr 6 '18 at 17:40
• Or perhaps I should move this over to PPCG...? – Selvek Apr 6 '18 at 17:51
• Hint 1 is live, should narrow down the possibilities a bit. – Selvek Apr 9 '18 at 16:20

Well, I could only get a partial answer

The number of each hound type is
Type Solid Spotted Mottled Brown 296 150 34 Grey 188 64 128 White 56 56 28

I could only solve till this, I didn't get the part about the division of plots.

• You have 270 spotted; you should have 270 mottled. – Peregrine Rook Apr 6 '18 at 18:34

Facts:

Total = 1000 Solid = 540 Mottled = 1/2 Solid = 540 / 2 = 270 Brown not spotted = 330 Spotted not brown = 120 In whites: solid = 2 * mottled In whites: spotted = 2 * mottled = solid in white Grey = 380 In grey: mottled = 2 * spotted

Deductions:

Spotted = Total - Solid - Mottled = 1000 - 540 - 270 = 190

The numbers has only one solution (forget the location for now):

| | Solid | Spotted | Mottled | | Brown | 168 | 70 | 162 | | Grey | 284 | 32 | 64 | | White | 88 | 88 | 44 |

And the locations can be:

| White Mottled | White Spotted | Grey Spotted | | Grey Mottled | Grey Solid | Brown Spotted | | Brown Mottled | Brown Solid | White Solid |