What is sub-algorithm?

Answer 1

It is an algorithm used by another algorithm as part of the second algorithm's operation.

As an example, an algorithm for finding the median value in a list of numbers might include sorting the numbers as a sub-algorithm: There are plenty of algorithms for sorting, and the specifics of the sorting does not matter to the "median value" algorithm, only that the numbers are sorted when the sub-algorithm is done.

For what an algorithm is, see related link.

Answer 2

A subalgorithm is a complete & independently defined algorithmic module which is used (or invoked or called) by some main algorithm or by some other subalgortihm

Answer 3

Don't be mean it will cause your brain to explode from all the hate and misery of being alone because your so mean. The real answer is pie 3.141528