Safu Tatu-Dimensional katika JavaScript

Hapa kuna mfano wa safu tatu-dimensional:

javascriptlet arr = [
  [
    ['a', 'b'],
    ['c', 'd'],
  ],
  [
    ['e', 'f'],
    ['g', 'h'],
  ],
  [
    ['i', 'j'],
    ['k', 'l'],
  ],
];

Ili kuchapisha vipengele kutoka kwenye safu kama hii, inahitajika kuandika mabano mraba matatu:

javascriptconsole.log(arr[0][0][0]); // itachapisha 'a'
console.log(arr[2][1][0]); // itachapisha 'k'
Задание 1

Imepangwa safu ifuatayo:

javascriptlet arr = [
  [
    [1, 2],
    [3, 4],
  ],
  [
    [5, 6],
    [7, 8],
  ],
];

Kwa kurejea kila kipengele cha safu, tafuta jumla ya vipengele vyake vyote.