JS useful

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// convert a number to linked lint in reverse
f = n => n ? { val: n % 10, next: f(n / 10 | 0) } : null;

console.log( f(465) ); // { val: 5, next: { val: 6, next: { val: 4, next: null } } }
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function ReverseListNodeToArray(listNode) {
        let returnedArray = []; // Initialise an array to return
        if (listNode.next != null) { // ListNode has level?
            // returnedArray = returnedArray.concat( // Merge with the node result
            //     ReverseListNodeToArray(listNode.next)
            // );
          returnedArray = [...returnedArray, ...ReverseListNodeToArray(listNode.next)];
        }
        returnedArray.push(listNode.val); // Add current node's value
        return returnedArray;
    }

console.log( ReverseListNodeToArray(f(465) ));
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/* stylelint-disable at-rule-no-unknown */
/* stylelint-disable color-named */
/* stylelint-disable color-no-hex */
/* stylelint-disable block-no-empty */
/* stylelint-disable declaration-block-no-duplicate-properties */
/* stylelint-disable declaration-block-no-shorthand-property-overrides */
/* stylelint-disable declaration-no-important */
/* stylelint-disable length-zero-no-unit */
/* stylelint-disable no-descending-specificity */
/* stylelint-disable no-duplicate-selectors */
/* stylelint-disable order/declaration-block-properties-alphabetical-order */
/* stylelint-disable property-no-vendor-prefix */
/* stylelint-disable rule-empty-line-before */
/* stylelint-disable selector-no-type */
/* stylelint-disable selector-no-universal */
/* stylelint-disable selector-pseudo-element-colon-notation */
/* stylelint-disable shorthand-property-no-redundant-values */
/* stylelint-disable value-list-comma-newline-after */
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