Question

I declared a struct which is supposed to be a pixel and it has 3 properties (x, y location and F intensity) like this:

struct pixel {
    int F,          // intensity from 0-255
    x,              // horizontal component           
    y;              // vertical component
};

Then I declared an 2D array of type pixel (the struct above) like this:

int N=100;
pixel image[N][N];

Then I used the following loop to assign values to x and y:

int count, k;

for (int i=0 ; i<N ; i++)
    for (int j=0 ; j<N ; j++)
    {
        k = j + i*N;
        image.x[k] = count;
        count++; 
     }

What did I do wrong?

Answer 1

The line

image.x[k] = count;

is incorrect. You declared a 2D array of pixels:

pixel image[N][N];

The way to access an element of the array is as follows:

image[i][j].x = count;

You do not need to calculate the flat index k yourself.