clingo返回最大子集

Question

我有以下代码：

1{p(1..10)}10.
:- p(I*2).

它显示了31个答案，但我只需要最大子集p(1) p(3) p(5) p(7) p(9).，我怎么做呢？

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Answer 1

你在寻找一个优化。最简单的修复方法是添加

#maximize{I:p(I)}.

结果是

Solving...
Answer: 1
p(9)
Optimization: -9
Answer: 2
p(5) p(9)
Optimization: -14
Answer: 3
p(7) p(9)
Optimization: -16
Answer: 4
p(5) p(7) p(9)
Optimization: -21
Answer: 5
p(1) p(5) p(7) p(9)
Optimization: -22
Answer: 6
p(3) p(5) p(7) p(9)
Optimization: -24
Answer: 7
p(1) p(3) p(5) p(7) p(9)
Optimization: -25
OPTIMUM FOUND

不要担心负分数，clingo将#maximize转换为#minimize，因此否定。那么#maximize{I:p(I)}.是做什么的呢？通常，您希望在I上最大化所有p(I)，在本例中，这是I之和。只要数一数

#maximize{1,I:p(I)}.

结果是

Answer: 1
p(9)
Optimization: -1
Answer: 2
p(5) p(9)
Optimization: -2
Answer: 3
p(5) p(7) p(9)
Optimization: -3
Answer: 4
p(3) p(5) p(7) p(9)
Optimization: -4
Answer: 5
p(1) p(3) p(5) p(7) p(9)
Optimization: -5
OPTIMUM FOUND