TIL C99 allows initializers like `int a[6] = { [4] = 29, [2] = 15 };`

TIL C99 allows following initializers. It’s described inDesignated Initializers.

int a[6] = { [4] = 29, [2] = 15 };
int widths[] = { [0 ... 9] = 1, [10 ... 99] = 2, [100] = 3 };