生成斐波那契数是 C

Question

I was practicing array in C. I have found a code mentioned bellow.

int main(void)
{
    int  numbers[10] = { 1, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
    int  i, j;

    **for (j = 0;  j < 10;  ++j)
        for (i = 0;  i < j;  ++i)
            numbers[j]  = numbers[j] +numbers[i];**

    for (j = 0;  j < 10;  ++j)
        printf("%i ", numbers[j]);

    printf("\n");

    return 0;
}

I know that it's a silly question. If anyone help me to understand the Bold marked for loop, I would be very grateful. Thanks in advance.

Answer 1

for (j = 0;  j < 10;  ++j)
    for (i = 0;  i < j;  ++i)
        numbers[j]  = numbers[j] +numbers[i];

The above loop will target particular position of the array and will add all the numbers one by one from 0th position to selected position.

Eventually you are not generating the Fibonacci sequence.

---

j =0
       1, 0, 0, 0, 0, 0, 0, 0, 0, 0

j = 1
       1, 1, 0, 0, 0, 0, 0, 0, 0, 0

j = 2
       1, 1, 2, 0, 0, 0, 0, 0, 0, 0

j = 3
       1, 1, 2, 4, 0, 0, 0, 0, 0, 0

j = 4
       1, 1, 2, 4, 8, 0, 0, 0, 0, 0

...so on