Easy Javascript solution
\n# Complexity\n- Time complexity: O(n)\n Add your time complexity here, e.g. O(n) \n\n- Space complexity: O(n)\n Add your space complexity here, e.g. O(n) \n\n
\n# Complexity\n- Time complexity: $$O(n)$$\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity: $$O(n)$$\n<!-- Add your space complexity here, e.g. $$O(n)$$ -->\n\n# Code\n```\n/**\n * @param {number[]} num\n * @param {number} k\n * @return {number[]}\n */\nvar addToArrayForm = function(num, k) {\n    let sum = BigInt(num.join(\'\')) + BigInt(k);\n    let convertSum = sum.toString().split(\'\').map((num) => parseInt(num));\n    return convertSum;\n};\n```
['JavaScript']