Chapter 14, Problem 1RQE

What type of recursive function do you think would be more difficult to debug; one that uses direct recursion or one that uses indirect recursion? Why?

Program Plan Intro

Recursive Function:

• The function has ability to call itself is called recursion function.
• It is a substitute method for reiteration.
• It replaces the loop statements, so without loop statement it executes the algorithm codes a number of times.
• Selection statement is used to make a decision for the execution of the recursion.
• There are two types of recursive functions. They are:
  • Direct recursion
  • Indirect recursion

Direct recursion:

When a function calls itself repeatedly until the condition becomes false is called as direct recursion.

Example:

//method definition

void test()

{

    //call a function

    test();

}

Indirect recursion:

When a function calls another function which in turn calls the same calling function is called as indirect recursion.

Example:

//method definition

void test()

{

    //call a function

    test1();

}

//method definition

void test1()

{

    //call a function

    test();

}

Explanation of Solution

Recursion that is difficult to debug:

The recursion that is difficult to debug is “Indirect recursion”.

Justification:

• Because, a function calls one function which is linked to another function.
• Since, a function can make multiple calls to a function; it is difficult to track the flow control of function that is being processed within the code.

Therefore, “Indirect recursion” is difficult to debug when compared to direct recursion.