Can we use global variable for recursion?

Global Variables in Recursion Function: If we write x as a global variable like below then also the result will be the same.

Can all recursive algorithms be iterative?

Can every recursive function be converted into an iterative function? Yes, any problem that can be solved recursively can also be solved through the use of iteration. The factorial function which we discussed here can also be implemented iteratively.

Can you define variables in a recursive function?

You can define a local variable in one recursive call, and the value of that will be accessible to all subsequent recursive calls.

Do recursive methods always have iterative solutions as well?

Recursion is good for programmers to understand a program, but many times they cause stackoverflows hence always prefer iteration over them. The fact is that recursion is rarely the most efficient approach to solving a problem, and iteration is almost always more efficient.

What are the properties of a recursive algorithm?

Like the robots of Asimov, all recursive algorithms must obey three important laws:

• A recursive algorithm must call itself, recursively.
• A recursive algorithm must have a base case.
• A recursive algorithm must change its state and move toward the base case.

When should we use iterative and when recursive?

If time complexity is the point of focus, and number of recursive calls would be large, it is better to use iteration. However, if time complexity is not an issue and shortness of code is, recursion would be the way to go.

Which of the following data structures is required to convert a recursive algorithm into an iterative one?

stack
Explanation: Since function calls are executed in Last In First Out order, stack is the data structure for converting recursive to iterative implementation.

How do you define a global variable in Python?

We declare a variable global by using the keyword global before a variable. All variables have the scope of the block, where they are declared and defined in. They can only be used after the point of their declaration.

Is it possible to transform recursion into an iterative algorithm?

Actually there is theorem that states that every recursive algorithm can be transformed into an equivalent iterative one (doing this requires mimicking the recursion iteratively using one or more stack data structures to hold parameters passed to recursive invocations). Thanks for contributing an answer to Stack Overflow!

Are there any optimization techniques to make recursion faster?

Some optimizations, like tail call optimization, make recursions faster but aren’t always possible, and aren’t implemented in all languages. Of course every recursion can be modeled as a kind of loop : that’s what the CPU will ultimately do. And the recursion itself, more directly, means putting the function calls and scopes in a stack.

Is it better to solve a problem recursively or not?

You will notice that some problems are easier to solve it recursively. Hint : Recursion is good when you are solving a problem that can be solved by divide and conquer technique. Besides being slower, recursion can also result in stack overflow errors depending on how deep it goes.

What is the difference between recursion and iteration in C++?

Recursion: Recursion has the overhead of repeated function calls, that is due to repetitive calling of the same function, the time complexity of the code increases manifold. Iteration: Iteration does not involve any such overhead.