Recap - Factorial

Factorial is a mathematical operation.

Factorial of n is the product of all positive integers less than or equal to n.

Important edge cases:

• Factorial of 0: 1 (by mathematical convention)
• Factorial of 1: 1 = 1

Examples:

• Factorial of 2: 2 = 1 × 2
• Factorial of 3: 6 = 1 × 2 × 3
• Factorial of 6: 720 = 1 × 2 × 3 × 4 × 5 × 6

Write a program that calculates the factorial of a given integer.

Important: Your program should handle all non-negative integers, including 0 and 1.

How to approach this problem:

1. Read an integer input using int(input())
2. Initialize a result variable to 1 (since multiplying by 1 doesn't change the result)
3. Use a loop to multiply all numbers from 1 to the input number
4. Print the final result (just the number, no extra text)

Example walkthrough:

For input 5:

• Start with result = 1
• Multiply by 1: result = 1 × 1 = 1
• Multiply by 2: result = 1 × 2 = 2
• Multiply by 3: result = 2 × 3 = 6
• Multiply by 4: result = 6 × 4 = 24
• Multiply by 5: result = 24 × 5 = 120

Key concepts you'll need:

• Multiplication assignment: result *<i>= i</i> (same as <i>result = result * </i>i)
• The range function: range(1, n + 1) includes numbers from 1 to n