Union-find

<div class="v"><header><b>UNION–FIND</b><span id="state"></span></header><main><div class="nodes" id="nodes"></div><div class="path" id="path"></div></main><footer>path compression shortens find</footer></div>

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let n=0;const paths=["D → C → B → A","D → A","A is representative"];function draw(){document.getElementById("nodes").innerHTML=["A","B","C","D"].map((v,i)=>"<b class=\""+(i===3||i===0?"active":"")+"\">"+v+"</b>").join("");document.getElementById("path").textContent=paths[n];document.getElementById("state").textContent=["find(D)","compress","next find"][n];n=(n+1)%3}draw();setInterval(draw,1150)