Gets items from the stack where the index is zero based and the top of
the stack is at an index of size()-1 with the bottom of the stack at an
index of 0.
Returns a SearchTechniques object that is used to create common techniques
for guiding searches such as Breadth First Searching and Depth
First Searching
An array of resourceIds indicating, for each operation, which resource is being used;
-1 is used to indicate that a particular opertation is not yet assigned to a resource.