Are there any reason to choose iterative algorithms over recursive ones

Question

I am more comfortable with implementing recursive methods over iterative ones. While studying for the exam, i implemented a recursive BFS(Breadth-First Search) using Queues, but while searching online for a recursive BFS that uses Queues, i kept on reading that BFS is an iterative algorithm not a recursive one. So is there any reason to choose one over the other?

Answer 1

Iterative and recursive both have same time complexity.difference is: recursive programs need more memory as each recursive call pushes state of the program into stack and stackoverflow may occur.but recursive code is easy to write and manage.You can reduce the space complexity of recursive program by using tail recursion.

Answer 2

Iterative is more efficient for the computer. Recursive is more efficient for the programmer and more elegant (perhaps).

The problem with recursive is each recursive call pushes the state/frame onto the call stack, which can quickly lead to resource exhaustion (stack overflow!) for deep recursion. But, the solutions are often easier to code and read.

Iterative performs better because it's all done in the local frame. However, converting recursive to iterative can reduce readabiity due to the introduction of variables to cater for the progression of the algorithm.

Chose whatever implementation is easiest to code and maintain. Only worry if you have a demonstrated problem.

Answer 3

Iterative implementations are usually faster. One example is fibonacci series. It's faster to implement it in a simple loop over a recursive solution.

More discussion here Recursion or Iteration?