Calculate Factorial with Recursion & Iteration in R

R Programming: Control Structure Exercise-13 with Solution

Write a R program function to calculate the factorial of a given number using both recursion and iteration (for loop).

Sample Solution :

R Programming Code :

# Function to calculate factorial using recursion
factorial_recursion <- function(n) {
    if (n == 0) {
        return(1)
    } else {
        return(n * factorial_recursion(n - 1))
    }
}

# Function to calculate factorial using iteration (for loop)
factorial_iteration <- function(n) {
    result <- 1
    for (i in 1:n) {
        result <- result * i
    }
    return(result)
}

# Test the functions with an example input
number <- 5
result_recursion <- factorial_recursion(number)
result_iteration <- factorial_iteration(number)

# Print the results
cat("Factorial of", number, "using recursion is:", result_recursion, "\n")
cat("Factorial of", number, "using iteration is:", result_iteration, "\n")

Output:

Factorial of 5 using recursion is: 120 
Factorial of 5 using iteration is: 120             

Explatnaion:

In the exercise above,

• The "factorial_recursion()" function calculates the factorial of a given number using recursion. It checks if the number is 0 (base case) and returns 1. Otherwise, it recursively calls itself with 'n - 1' until 'n' becomes 0.
• The "factorial_iteration()" function calculates the factorial of a given number using iteration (for loop). It initializes a variable 'result' to 1 and then iterates from 1 to 'n', multiplying 'result' by each number in the loop.
• Both functions are tested with an example input (number = 5), and the results are printed to the console.

R Programming Code Editor:

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