Unique Sorted

unique-sorted.ts

interface Tree {
    [index: string]: number | Tree;
}

const getUniqueSortedNumbers = (tree: Tree, items: number[] = []): number[] => {
    Object.keys(tree).map((key: string) => 
        typeof tree[key] === 'object' 
            ? getUniqueSortedNumbers(tree[key] as Tree, items) 
            : items.indexOf(tree[key] as number) <= 0 && items.push(tree[key] as number)
    )

    return items.sort((a, b ) => a < b ? -1 : 1);
}

const numbers = getUniqueSortedNumbers({
  a: {
    x: 3,
    y: {
      d: 2,
      e: 2,
      f: {
        g: 4
      },
      z: 8
    }
  }
});

console.log(numbers);