Depth-first search

<div class="v"><header><b>DEPTH-FIRST SEARCH</b><span id="state"></span></header><main><div class="dbranches" id="dbranches"></div><div class="dstack" id="dstack"></div></main><footer>descend → backtrack → descend</footer></div>

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const stages=[{at:"A",stack:"A"},{at:"B",stack:"A → B"},{at:"D",stack:"A → B → D"},{at:"C",stack:"A → C"},{at:"E",stack:"A → C → E"}];let step=0;function row(names,at,visited){return "<div class=drow>"+names.map((v,i)=>"<b class='"+(v===at?"active":visited.includes(v)?"muted":"")+"'>"+v+"</b>"+(i<2?"<i></i>":"")).join("")+"</div>"}function draw(){const s=stages[step],visited=stages.slice(0,step).map(x=>x.at);document.getElementById("dbranches").innerHTML=row(["A","B","D"],s.at,visited)+row(["A","C","E"],s.at,visited);document.getElementById("dstack").textContent="stack: "+s.stack;document.getElementById("state").textContent=step===3?"backtrack":"visit "+s.at;step=(step+1)%stages.length}draw();setInterval(draw,900)