find-node.js

const findNode = (tree, value) => {
  let found = false;

  if (tree.value === value) {
    return true;
  }

  for (var index = 0; index < tree.children.length; index++) {
    const element = tree.children[index];
    found = findNode(element, value);
    if (found) {
      break;
    }
  }

  return found;
};

/* example tree

   let tree = {
    name: 'A',
    value: 4,
    children: [
        {
            name: 'B', value: 7,
            children: [{name: 'C', value: 9, children: []}]
        },
        {
            name: 'D', value: 11,
            children: [{name: 'E', value: 9, children: []}]
        },
        {name: 'F', value: 55, children: []},
        {
            name: 'G', value: 65,
            children: [
                {name: 'H', value: 21, children: []},
                {name: 'I', value: 33, children: []}
            ]
        }
    ]
}; */