Factorial of a number n is the product of all integers from 1 to n. In this article, we will learn how to find the factorial of a number using iteration in C++.
Example
Input: 5
Output: Factorial of 5 is 120
Factorial of Number Using Iteration in C++
To find the factorial of a given number we can use loops. First, initialize the factorial variable to 1, and then iterate using a loop from 1 to n, and in each iteration, multiply the iteration number with factorial and update the factorial with the new value.
C++ Program to Find Factorial Using Iteration
The below program shows how we can find the factorial of a given number using the iteration method.
// C++ program to find factorial of a number using iteration #include <iostream> using namespace std;
int main()
{ // number n whose factorial needs to be find
int n = 5;
// initialize fact variable with 1
int fact = 1;
// loop calculating factorial
for ( int i = 1; i <= n; i++) {
fact = fact * i;
}
// print the factorial of n
cout << "Factorial of " << n << " is " << fact << endl;
return 0;
} |
Factorial of 5 is 120
Time Complexity: O(N), where N is the given number
Auxiliary Space: O(1)