A place to air possible concerns or difficulties in understanding ProjectEuler problems. This forum is not meant to publish solutions. This forum is NOT meant to discuss solution methods or giving hints how a problem can be solved.

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There seems to be some ambiguity. Is 'the upper row' the same as 'the top row'? ie does the ant drop the seed on the 2nd row or on the 5th row (measured from the bottom)?

I am inclined to think it's the 5th, though I would like a definite answer.

my ant always needs between 380 and 480 steps but i just dont know how to enter that result.
"Give your answer rounded to 6 decimal places."
what does that mean?!?!
i think that sentence has nothing to do with understanding the problem - i just want to know how to enter my result - it's annoying me!

example of my ant walking around randomly (the last steps)

Suppose you flipped a coin 11 times and counted how many heads you got. Most of the time you would get somewhere between 4 and 7 - but the exact average number of heads you would get is exactly 5.5.

You have to specify how many steps the ant would average if you ran the simulation a very large number of times.

Ok, so I think I've got a handle on the maths required for this, but my very very simple brute force simulation is producing some odd values.

So, starting from the middle square:
00000
00000
00X00
00000
11111

would the actual expected value of the number of turns it takes to reach the N'th item on the bottom row be more along the lines of {~27,~24,~19,~24,~27} turns? Because that seems really high to me.

The equivalent 3x3 scenario is giving me the equally odd numbers:
000
0x0
111

E = {~7,~4.5,~7}

Am I wildly off base here & should look into my brute force simulation, or are these close enough to the actual values that I can start delving into formulas & good stuff?

I haven't checked the numbers exactly, but they don't look strange to me. For example, in the 3x3 case, if you are aiming for the bottom square, three quarters of the time you are moving further away from it in the first turn, so you would expect it would take several more turns before you get back there. For the two corner squares, even after you finally reach something adjacent to the corner, two thirds of the time you move away again.

I think you should be able to trust your brute force program.