The problem task in Russian isn't equal to the problem task in English. The English text have following sentence: "You have to put the fence in the minimum number of squares so that the goat will be able to visit exactly K squares." It means that our region built could contain only K squares and something else, for example halves squares (as in example). But in the problem task in Russian this sentence is as follows:
"Требуется, поставив минимальное число секций, предоставить козлу участок ровно из K квадратов."
It means that the region contains only K squares and nothing else.

I think that this sentence should be rewritten as follows:
"Требуется, поставив минимальное число секций, предоставить козлу возможность посетить ровно K квадратов."


And something else.

English sentence contains phrase: "to put the fence in the minimum number of squares". But how should we count number of squares if the fence is put on the bound of two squares?!!

"You can build a fence in some of the garden's elementary squares." (English version)

"Хозяева козла умеют ставить секции забора в отдельных элементарных квадратах на поле." (Russian version)

So the fence consists of the unit squares, not of line segments.

Sample test can be written as follows:
..X.
.X.X
X..X
.XX.

Edited by author 03.10.2009 17:22