# Recursion in CPP

When a function calls itself within its function block, it is called as self calling by a function. This whole process of self calling by a function is often termed as Recursion. Recursion is used to create a loop like behavior using a function and without using loop statements.

Syntax:

Return_type function_Name(parameters)

{

code to be executed;

function_Name(parameters);

}

Example: Factorial of 5 using Recursion.

#include <iostream.h> using namespace std;   int main() { int factorial(int); int fact=factorial(5); cout<<"Factorial of 5 is: "<<fact<<endl; return 0; }   int factorial(int n) { if(n<0) return(-1); if(n==0) return(1); else { return(n*factorial(n-1)); } }

Output

Factorial of 5 is: 120