A graph represented using an associative array, keyed by the number, and an array key-value pair

main.tsx

type Graph<K, V> = Map<K, [K, V][]>;

type BinaryTreeNode<T> = {
  left?: [T] | null | undefined;
  right?: [T] | null | undefined;
};

type BinaryTree<K> = Map<K, BinaryTreeNode<K>>;

const bst: BinaryTree<number> = new Map();

function insert(
  graph: BinaryTree<number>,
  { root, toInsert }: { root: number; toInsert: number }
) {
  const value = graph.get(root);
  if (!value) {
    graph.set(toInsert, {});
  } else {
    if (toInsert < root) {
      if (!value.left) {
        value.left = [toInsert];
        graph.set(toInsert, {});
      } else {
        insert(graph, { root: value.left[0], toInsert });
      }
    } else if (toInsert > root) {
      if (!value.right) {
        value.right = [toInsert];
        graph.set(toInsert, {});
      } else {
        insert(graph, { root: value.right[0], toInsert });
      }
    }
  }
}

function* traverse(graph: BinaryTree<number>, root: number) {
  const node = graph.get(root);
  if (node) {
    if (node.left) {
      yield* traverse(graph, node.left[0]);
    }
    yield root;
    if (node.right) {
      yield* traverse(graph, node.right[0]);
    }
  }
}

insert(bst, { root: 1, toInsert: 1 });
insert(bst, { root: 1, toInsert: 2 });
insert(bst, { root: 1, toInsert: 50 });
insert(bst, { root: 1, toInsert: 45 });
insert(bst, { root: 1, toInsert: 30 });
insert(bst, { root: 1, toInsert: 10 });
console.log([...traverse(bst, 1)]);