What is simulation recursion in C?

Answer 1

The factorial f(n) = n * (n-1) * (n-2) * .. 1. For example factorial 5 (written as 5!) = 5 x 4 x 3 x 2 x 1 = 120. The function below returns the factorial of the parameter n. int factorial( int n) {

if (n==1)

return 1

else

return n* factorial( n-1) ;

}

Answer 2

It is a function that calls itself.

Each time the function executes itself, it pushes a copy of itself onto the stack. This stack as a specific number of slots it can hold. A recursive function must either return before it has called itself x number of times, or it will cause a stack-overflow exception.

This is true in many C-like languages such as C++, Java, C#, Visual Basic .NET.

Example below:

# include

int factorial(unsigned int number)

{

// This is the exit clause. It guarantees a stack-overflow will not occur.

if(number <= 1)

{

return 1;

}

return number * factorial(number - 1);

}

void main()

{

int x = 5;

printf("factorial of %d is %d",x,factorial(x));

}

Each time a function calls itself, the overhead of it calling itself and adding itself to the stack increases. It is often more efficient to use a loop than use recursion. It is also less error-prone.

Example (many times faster without recursion):

int factorial(unsigned int number)

{

int factorialnumber = 1;

for(int index = number - 1; (index > 0) && (number > 0); --index)

{

// if number divides evenly into index... % operator is modulus, or division remainder.

if ((number % index) == 0)

{

factorialnumber = factorialnumber * index;

number = number / index; // this will never have a decimal.

}

}

return factorialnumber;

}

void main()

{

int x = 5;

printf("factorial of %d is %d",x,factorial(x));

}

Answer 3

Well to explain it I'll use an example

power(int n,int exp)

{

if(exp==0)

{

return 1;

}

else

{

return n*power(n,exp-1);

}

}

so all you do is

function(parameters)

{

//check for base case

//if not base case then do the update and recursive call

}

Answer 4

Recursion is a powerful concept in computer programming that refers to a function calling itself. A recursive function is a function that calls itself, either directly or indirectly, to solve a problem.

A recursive function consists of a base case and a recursive case. The base case is the termination condition of the recursion. It is a condition where the function does not call itself and instead returns a value or performs some other action. In the recursive case, the function calls itself to solve a smaller instance of the problem.

Recursion can be used to solve problems that have a self-similar structure, such as searching a tree, finding the factorial of a number, or generating permutations of a string.

Let's take a simple example of a recursive function in C Programming to calculate the factorial of a number. The factorial of a non-negative integer n is the product of all positive integers from 1 to n.

Here is the code for a recursive function to calculate the factorial of a number:

int factorial(int n) {

// Base case

if (n == 0) {

  return 1;

}

// Recursive case

else {

  return n * factorial(n - 1);

}

}

In the code above, the factorial function takes an integer n as input and returns the factorial of n. The function first checks if n is equal to 0, which is the base case. If n is 0, the function returns 1. If n is not 0, the function enters the recursive case and calls itself with n-1 as input. The result of the recursive call is multiplied by n and returned as the result of the current call.

When the factorial function is called with a non-negative integer n, the function will keep calling itself recursively until n becomes 0. The base case is triggered at this point, and the function returns 1. Each recursive call's results are multiplied to calculate the final result.

It is important to note that recursive functions can be less efficient than non-recursive functions, as each recursive call requires additional memory for the function call stack. Additionally, recursive functions may lead to infinite recursion if the base case is not properly defined or if there is an error in the recursion logic.

In summary, recursion is a powerful concept in computer programming that can be used to solve problems that have a self-similar structure. Recursive functions in C programming consist of base and recursive cases. They can be used to solve problems such as searching a tree, finding a number's factorial, or generating a string's permutations. It is important to carefully define the base case and ensure that there is no infinite recursion to ensure that the recursive function works correctly.

Recursion can be very useful for solving problems that have a self-similar structure, but it can also lead to stack overflow errors and decreased efficiency. It can be used to write elegant and concise code, but it can also be difficult to debug and understand, especially for complex recursive functions.

Answer 5

Recursion, in any programming language, refers to, most commonly, a call to a function inside that function, (i.e a function calling itself)

Answer 6

w.a.p. to find factorial of a number using recursion

Answer 7

what is simulating recursion