[SOLVED]2D array assignment(C++)

[Donutslayer7]

A pretty basic question, I know: when I declare a 2D array...

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int map[5][5] =
{
          {0,0,0,0,0},
          {0,0,0,0,0},
          {0,0,0,0,0},
          {0,0,0,0,0},
          {0,0,0,0,0}
}

the code is fine, when I assign part of an array...

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map[3][2] = 1;

but I want to know if there is a way I can assign all of an arrays values at once much like declaring it...

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map[5][5] = //this doesn't work
{
...
}

I know I can use a for loop to loop through the array, but I just want to know if it's possible to assign it all at once

[Bakkon]

I'm about 100% sure there's not a shorthand way to do it and you're required to loop through each element. The only way to assign a value to everything at once is when it's first defined, such as:

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int array[25] = {0};

This will initialize each element to 0, but there's no way to do something like that after it's already defined.

edit: Clarification, if you did this:

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int array[25] = {1};

It will initialize element [0] to 1 and the rest of the elements to 0.

[GroundUpEngine]

I'm about 100% sure there's not a shorthand way to do it and you're required to loop through each element.

That's the way I learned too

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-- e.g.

for(int i = 0; i < 5; i++)
{
    for(int j = 0; j < 5; j++)
    {
         map[i][j] = 0;
    }
}

[avansc]

calloc

[qpHalcy0n]

You probably would not want to calloc. You'd want to memset in this case.

[RyanPridgeon]

You could create a seperate array such as

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int preset[3][3] = {
  { 0, 0, 0 },
  { 0, 1, 2 },
  { 1, 1, 2 }
};

or whatever, then use memcpy(), or your own function to copy the preset array into the array you're working with, such as

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int level[3][3];
memcpy(level, preset, sizeof(preset));

Which will copy it to be identical to your preset array, not matter where you are in the code (as long as preset is in scope).

[avansc]

^^, yeah if the mem was already allocated, and if you wanted anything other than 0.
but yeah, memset would be better.

[eatcomics]

Or you could use a for loop, like the others said... But I guess you can do a memset

[Donutslayer7]

ah, copying a previous array, great idea, thanks, I'll look into this memset function