Factorial using Addition

Question

I am attempting to create a C code that finds the factorial of a integer so that I may convert my code to assembly language. My code seems to \'multiply\' the second integer twi

Answer 1

The steps for the computation are incorrect: it is simpler to start from the low factors to the larger ones.

Here is a corrected version:

#include 

#define N 10

int main() {
    int i, j, num1, sum;

    num1 = 1;
    sum = 1;
    for (i = 1; i <= N; i++) {
        sum = 0;
        for (j = 0; j < i; j++) {
            sum += num1;
        }
        printf("%d! -> %d\n", i, sum);
        printf("--------------\n");
        num1 = sum;
    }
    return 0;
}

Output:

1! -> 1
--------------
2! -> 2
--------------
3! -> 6
--------------
4! -> 24
--------------
5! -> 120
--------------
6! -> 720
--------------
7! -> 5040
--------------
8! -> 40320
--------------
9! -> 362880
--------------
10! -> 3628800
--------------