Error with expected operator before token - c

Question

The error is telling me I'm missing an operator somewhere, but I simply cannot see it so I figured some fresh eyes could help me find it.
Code snippet:
static int min_val, max_val;
struct arrNum
{
int charged;
int count;
};
static struct arrNum nums[];
static int max_num = 0;
static void sort_order(int iNum)
{
if (iNum < 0)
return;
if (iNum > max_num)
max_num = iNum;
struct arrNum nums[iNum].charged = 1;
struct arrNums nums[iNum].count++;
return;
}
Errors:
mergeSort.c: In function 'sort_order':
mergeSort.c:32:29: error: expected '=', ',', ';', 'asm' or '__attribute__' before '.' token
struct arrNum nums[iNum].charged = 1;
^
mergeSort.c:32:29: error: expected expression before '.' token
mergeSort.c:33:30: error: expected '=', ',', ';', 'asm' or '__attribute__' before '.' token
struct arrNums nums[iNum].count++;
^
mergeSort.c:33:30: error: expected expression before '.' token
Any help is welcome. Thank you!

Answer 1

here is a version of the code with comments:
// following two statements will cause the compiler to raise
// warning messages because this statements
// declare the variables, but they are never used
static int min_val;
static int max_val;
// define a struct with two fields
struct arrNum
{
int charged;
int count;
};
// declare an instance of a pointer to a struct
// actually want an array of `struct arrNum`
// so need a number between the '[' and ']'
// it must be given a size that is at least 1 greater
// than the highest value of 'iNum'
static struct arrNum nums[];
static int max_num = 0;
// following line will raise a compiler warning
// because 'static' function can only be referenced in the current file
// and nothing in the posted code calls it.
static void sort_order(int iNum)
{
if (iNum < 0)
return;
if (iNum > max_num)
max_num = iNum;
// note: both following statements are
// writing into 'la la land'
// because all that has been declared for
// 'nums[]' is a pointer
// and because it is declared 'static'
// is initialized to 0
// so executing either of these statements
// will result in a seg fault event
nums[iNum].charged = 1; // nums[] already declared, so don't declare it again
nums[iNum].count++; // nums[] already declared, so don't declare it again
}