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This is true for IDA* and backtracking. Branch-and-bound needs some communication for broadcasting the bound values.

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Note that the nodes assigned to a processor cover all parts of the tree, so this leads to a wide spreaded distribution of the search-frontier over the whole system.

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More precisely, AIDA* bundles up to five nodes in a work packet. PIDA* transfers the highest unsearched subtree; alternative stack-splitting strategies are discussed in [7][4].

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In practice, we simulate breadth-first search by iterative-deepening.

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Problem #95, h=35, g=57. AIDA* solution time: 243 secs.