[Solved] Sum of factorials in Java [closed]

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This is where methods might come in handy. First an outer loop because you’re counting down (from 4, in this example).

static final int NR = 4; //for example

static void main(String[] args) {
    int total = 0;
    for (int i = NR; i > 0; i--)
        total += calculateFactorial(i); //i += j; is the same as i = i + j;
    System.out.println("Answer: " + total);
}

Now it looks way easier, right? The code suddenly became readable. Now for calculateFactorial(int nr) all we have to do is calculate 4 * 3 * 2 * 1 (for the factorial of 4, that is):

public static int calculateFactorial(int nr) {
    int factorialTotal = 1;
    for (int i = nr; i > 0; i--)
        factorialTotal *= i; //i *= j; is the same as i = i * j;
    return factorialTotal;
}

Methods just made code easy to read and write. I’d suggest you read a book like Clean Code

solved Sum of factorials in Java [closed]