When a problem can be divided into a set of sub problems, where each sub problem can be solved separately and a combination of these will be a solution, AND-OR graphs or AND – OR trees are used for representing the solution.
The decomposition of the problem or problem reduction generates AND arcs.
The figure shows an AND-OR graph
To pass any exam, we have two options, either cheating or hard work.
In this graph we are given two choices, first do cheating or (The red line) work hard and (The arc) pass.
When we have more than one choice and we have to pick one, we apply OR condition to choose one.(That’s what we did here).
Basically the ARC here denote AND condition.
Here we have replicated the arc between the work hard and the pass because by doing the hard work possibility of passing an exam is more than cheating.
When a problem can be divided into a set of sub problems, where each sub problem can be solved separately and a combination of these will be a solution, AND-OR graphs or AND – OR trees are used for representing the solution.
The decomposition of the problem or problem reduction generates AND arcs.
The figure shows an AND-OR graph