Nested list from a flat array

pages.js

var pages = [{
    title: "alice",
    depth: 0
  },{
    title: "bob",
    depth: 1
  },{
    title: "charles",
    depth: 1
  },{
    title: "delilah",
    depth: 1
  },{
    title: "everett",
    depth: 0
  },{
    title: "francais",
    depth: 1
  },{
    title: "gloria",
    depth: 1
  },{
    title: "harold",
    depth: 1
  },{
    title: "ingrid",
    depth: 2
  },{
    title: "jake",
    depth: 0
  }];

var html = [];

for (var i=0;i<pages.length;i++) {
  var p = pages[i],
      q = pages[i+1],
      r = true;
  if (q) {
    if (q.depth > p.depth) {
      html.push("<li>" + p.title + "<ol>");
      r = false;
    } else if (q.depth < p.depth) {
      html.push("<li>" + p.title + "</li>");
      for (j=0;j<p.depth;j++) html.push("</li></ol>");
      r = false;
    }
  }
  if (r) {
    html.push("<li>" + p.title + "</li>");
  }
}
var ol = document.createElement("ol");
ol.innerHTML = html.join("");
document.body.appendChild(ol);