Ultrasound or thermoacoustic refrigeration uses a resonating sound wave to induce a thermal gradient.

Mark S. Reed has written:

'Measurements with wire mesh stacks in thermoacoustic prime movers'

A single dimensional array is an array of items. A two-dimensional array is an array of arrays of items.

An irregular dimensional array is a special type of multi-dimensional array.

First we must understand that a multi-dimensional array is just an array of arrays. Each element in the array is, itself, an array of elements.

A regular multi-dimensional array will be an array of size n, with each element containing a separate array of size m. That is, each sub-array has the same size.

An irregular multi-dimensional array will be a multi-dimensional array in which each sub-array does not contain the same number of elements.

Regular array:
array[0] = new array{0, 1, 2}
array[1] = new array{3, 4, 5}
array[2] = new array{6, 7, 8}
array[3] = new array{9, 10, 11}

This regular array is an array of size 4 in which each sub-array is of size 3.


Irregular array:
array[0] = new array{0, 1, 2}
array[1] = new array{3, 4}
array[2] = new array{5, 6, 7}
array[3] = new array{8, 9, 10, 11}

This irregular array is an array of size 4 in which the size of each sub-array is not the same.

Option 1) Use a temporary variable:

int x = array[i];

array[i] = array[i+1];

array[i+1] = x;

Option 2) Use bit operators:

array[i] ^= array[i+1] ^= array[i];