Is there a typo in the induction section? Should `simplifyTree` and `simplifyGraph` be the same function?

function simplifyTree(root: Node): Node {

  let newChildren = [] as Array<Node>;

  for (const child of root.children) {
    const simplifiedChild = simplifyGraph(child);
  
    if (shouldContract(simplifiedChild)) {
      for (const grandChild of simplifiedChild.children) {
        newChildren.push(grandChild);    
      }
    } else {
      newChildren.push(simplifiedChild);
    }
  }

  root.children = newChildren;

  return root;
}