Question

I have five arrays.

int Circle_list[] = { Color.BLACK, 20, 20, 50 };
int Rect_list[] = { Color.BLUE, 80, 50, 115, 150 };
int Tri_list[] = { Color.RED, 190, 210, 150, 230, 140, 270 };
int mixColor[];
int mixCoor[];

Now, I want to add the first element(color) from Circle_list[], Rect_list[] and Tri_list[] into mixColor[]. And add all rest numbers into mixCoor[].

How can I do that? Does for loop available for this?

Answer 1

// if you really want to use primitives instead of ArrayLists, this will work:

int mixColor[] = { Circle_list[0], Rect_list[0], Tri_list[0] };
int mixCoor[] = new int[Circle_list.length + Rect_list.length + Tri_list.length - 3];

int i, j=0;

for(i=1; i<Circle_list.length; ++i, j++) {
    mixCoor[j] = Circle_list[i];
}
for(i=1; i<Rect_list.length; ++i, j++) {
    mixCoor[j] = Rect_list[i];
}
for(i=1; i<Tri_list.length; ++i, j++) {
    mixCoor[j] = Tri_list[i];
}

// OR more general solution:

j = 0;
int[][] shapes = {Circle_list, Rect_list, Tri_list};
for (int[] shape : shapes) {
    for(i=1; i<shape.length; ++i, j++) {
        mixCoor[j] = shape[i];
    }
}

// If you want to use ArrayLists instead, see also: How to convert List<Integer> to int[] in Java?