Beam search: is a heuristic search algorithm that is an optimization of best-first search that reduces its memory requirement. Beam stack search: integrates backtracking with beam search. Best-first search: traverses a graph in the order of likely importance using a priority queue. Bidirectional search: find the shortest path from an initial vertex to a goal vertex in a directed graph. Bloom filter: a constant time and memory check to see whether a given element exists in a set.
Estimates vary as to how long it took to build the Taj Mahal. Some historians state that it took only 14 years to build it, from 1631-1645, but a more realistic figure is probably 22 years, being completed in 1653.
In a way, the markble used to build the monument was more like a mosaic. Smaller slabs and pieces were carved or etched and then set close to each other. It is reported that over 20,000 craftsmen and artisans were used to complete the Taj Mahal. This over a span of 20 years and a cost of around 7 million U.S dollars.