var aiHeadCnts = [];
for(let headCur of document.querySelectorAll('[class^="mw-heading"'))
{
let bNewHeadLevel = false;
let iOldHeadCurLevel = aiHeadCnts.length;
let iLevelOfCurHead = parseInt(Array.from(headCur.classList).find((strCurClass) => /mw-heading\d+/i.test(strCurClass)).replace(/mw-heading/i, '')) - 1;
if(iLevelOfCurHead < iOldHeadCurLevel)
aiHeadCnts = aiHeadCnts.slice(0, iLevelOfCurHead);
else if(iLevelOfCurHead > iOldHeadCurLevel)
{
aiHeadCnts = aiHeadCnts.concat(new Array(iLevelOfCurHead - iOldHeadCurLevel).fill(1));
bNewHeadLevel = true;
}
if(!bNewHeadLevel)
aiHeadCnts[iLevelOfCurHead - 1]++;
let spanCurLabel = headCur.querySelector('.header-label');
if(spanCurLabel == null)
{
spanCurLabel = document.createElement("span");
spanCurLabel.className = "header-label";
headCur.prepend(spanCurLabel);
}
spanCurLabel.innerText = aiHeadCnts.join('.')
}