Heap priority queue

<div class="v"><header><b>MAX HEAP</b><span id="state"></span></header><main><div class="tree" id="tree"></div><div class="insert">insert <b>9</b> ↑</div></main><footer>parent ≥ children</footer></div>

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const steps=[[8,6,7,2,4,5,9],[8,6,9,2,4,5,7],[9,6,8,2,4,5,7]];let s=0;function draw(){document.getElementById("tree").innerHTML=steps[s].map((v,i)=>"<div class=\"node "+(v===9?"active":"")+"\">"+v+"</div>").join("");document.getElementById("state").textContent=["append","swap parent","root restored"][s];s=(s+1)%3}draw();setInterval(draw,1050)