Initializing an array of struct in one line? (in C)

Question

I have a 2d array of structs like this,

MapStruct myMap[50][50];

So we can initialize like this,

myMap[0][0].left = 0;
myMap[0][0].up = 1;
myMap[0][0].right = 5;

I know that I can also use the below example,

MapStruct myMap[50][50] = { {0,1,5}, {2,3,7}, {9,11,8} ... };

But the problem is that there are significant empty spots in this 50x50 structure. So for example maybe from [30][40] up to [40][50] is empty and some other points here and there are empty so with the above bracket notation i have to leave empty brackets like this {},{},{} for those empty spots.

Now my question is is there a way to initialize the like below?

myMap[0][0] = {0, 1, 5}; // gives a syntax error

Saves two lines per point I'd be pretty happy with that.

Ps: I'm using the indices myMap[x][y] as keys like a dictionary object so I can't just get rid of those empty ones in the middle because that changes the indices.

Answer 1

C99 allows

myMap[0][0] = (MapStruct){0, 1, 5};

If you are restricted to C90, you can use an helper function.

mypMap[4][2] = makeStruct(3, 6, 9);

But note that

MapStruct myMap[50][50];

in a function won't initialize the array with 0 values if there are no initializer, so you'll have to use

MapStruct myMap[50][50] = {0};

And also note that one may wonder if it is wize to allocate such big arrays on the stack.