4. What is meant by the optimal substructure property in the context of dynamic programming. Using the dynamic programming technique, devise an algorithm for finding the least cost way to convert a given string X to another string Y . The allowed operations are INSERT, DELETE, REPLACE, and COPY with costs of 2, 3, 4, and 1 respectively for each of the above operations. Show the recurrence relation and then write a memoized program. Finally, add enough steps to be able to print the solution.

Through the process of sedimentation,sediment is turned back to rock to form sedimentation.the process of sedimentation is: > deposition-where fragments were deposited into the river or sea under gravity or travelling agent such as wind or water. > sedimentation-the fragments deposited in the river sedimented and accumulate> compaction-the layers of fragments deposited undergoes compaction due to the weight if the upper layers> cementation-chemical substance of the fragments such as cement dissolved into the water and cement the other fragments together to form sedimentary rock.thus,cementation and compaction are the process.on the other hand, transformation only occur when a rock under goes metamorphism(compaction or extreme heat).while recrystillization occurs when a rock is melted and cooled down,which also requires metamorphism to take place.hope it !

  answer clean and tinned with melted solder;