Recap - Factorial

Part of the Fundamentals section of Coddy's R journey — lesson 42 of 78.

Challenge

Easy

Read a number n from input. Calculate and print the factorial of n using a loop.

The factorial of a number n (written as n!) is the product of all positive integers from 1 to n. For example:

5! = 5 × 4 × 3 × 2 × 1 = 120
3! = 3 × 2 × 1 = 6
1! = 1
6! = 6 × 5 × 4 × 3 × 2 × 1 = 720.

Print the final result using print().

Try it yourself

# Read input
con <- file("stdin", "r")
n <- as.integer(suppressWarnings(readLines(con, n = 1)))

# Initialize result
result <- 1

# TODO: Write your code here to calculate the factorial using a loop


# Print the result
print(result)

All lessons in Fundamentals

1Introduction to R

What is R?Hello World Comments in R

4Operators Part 2

Logical Operators (AND, OR)Logical Operators Part 2 (NOT)Recap - Simple Logic Vectorized Logic Part 1 Vectorized Logic Part 2

7Bill Split Calculator

Welcome Message Getting User Input

Calculating The Tip And Total

Splitting The Bill

Formatted Output (sprintf)

10FizzBuzz with a Twist

Game Overview The FizzBuzz Function

Looping Through Numbers

Adding The Twist

13Vectors Advanced

Vector Slicing and Indexing Logical Indexing Vector Arithmetic & Recycling The %in% Operator