Simplest algorithm for computing the resultant of a boolean expression?

  • Thread starter spikenigma
  • Start date

let's take something simple, for example:

(a>b) && ((b>c) && c>d) || (d > c)

Intuitively, it's easy to work out given the values of a, b, c and d and just evaluating the brackets in order of precedence.


Is b > c?? then is c > d
Then in addition to the above answer being true is a > b?
Then despite the earlier answer is d > c?
If true return true, if false return false.

But surely there is an elegant, simple algorithm for working this out computationally?

Could you for example take each expression, number them in terms of their evaluation step then evaluate in n steps based on [some factor] to get the answer?


1) b>c, and then because of [factor], compute &&
2) c>d, and then because of [factor], compute &&
3) a>b, and then because of [factor], compute ||
4) d > c
5) answer

I know the factor is sign-right or sign-left of the expression and it could be used to create an algorithm.

But has anybody got anything more elegant?


Insights Author
2018 Award
The problem itself is NP complete, i.e. no algorithm is known, which decides in polynomial time whether a general Boolean expression is satisfiable or not, see This means in return, that given a certain example, we can probably use specific properties to be faster, but not in general.

Want to reply to this thread?

"Simplest algorithm for computing the resultant of a boolean expression?" You must log in or register to reply here.

Physics Forums Values

We Value Quality
• Topics based on mainstream science
• Proper English grammar and spelling
We Value Civility
• Positive and compassionate attitudes
• Patience while debating
We Value Productivity
• Disciplined to remain on-topic
• Recognition of own weaknesses
• Solo and co-op problem solving

Hot Threads