#include <algorithm>
#include <array>
#include <iostream>
 
using namespace std;
 
#define WIDTH 3
#define HEIGHT 2
 
int main() {
	const array<array<int, HEIGHT>, WIDTH> pCells = { 1, 2, 11, 12, 21, 22 };
	int lCells[WIDTH * HEIGHT];
 
	for_each(begin(lCells), end(lCells), [i = cbegin(pCells), j = cbegin(pCells)->cbegin()](auto& it) mutable {
		if(j == i->cend()) j = (++i)->cbegin();
 
		it = *j++;
	});
 
	for(const auto& i : lCells) {
		cout << i << ' ';
	}
}

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