Recursion in C Programming

In this tutorial, we will study what is recursion in c programming, the structure of the recursion function, the advantages and disadvantages of recursion in c, the types of recursion, and the factorial of a number using recursion.

Recursion in C Programming

Recursion is a process in which the function calls itself. Recursion is used to solve a problem by dividing it into small parts. Such functions which call themselves are called recursive functions.

Structure of Recursive Function

return type myFunction(Parameters-list) { statement 1; statement 2; … statement N; myFunction(Arguments-list); … other statements; }

Advantages and Disadvantages of Recursion in c

Advantages

• If we solve a problem through Recursion, then there is no need to call the function again and again. If we call the function 1 time, it keeps calling itself till the end result comes.

• The same problem is easily solved in recursion.

Disadvantages

• Recursive programs are slower than normal programs.

• Requires consuming extra memory.

Types of Recursion in C

Direct Recursion

Direct recursion is a recursion in which a function calls itself.

return_type MyFunction(parameter-list) { statements; MyFunction(argument-list); other statements; }

Indirect Recursion

In this, one function calls another function which in return calls it itself.

First Function

return_type FunctionOne(parameter-list) { statements; FunctionTwo(argument-list); other statements; }

Second Function

return_type FunctionTwo(parameter-list) { statements; FunctionOne(argument-list); other statements; }

Factorial of a Number Using Recursion

#include <stdio.h> #include <conio.h> long int fact(int n); int main() { int n; printf("Enter a positive integer: "); scanf("%d", &n); printf("Factorial of %d = %ld", n, fact(n)); return 0; } long int fact(int n) { if (n >= 1) return n*fact(n-1); else return 1; }

Output

Enter a positive integer: 4 Factorial of 4 = 24

Originally posted on alimammiya.hashnode.dev