DFS

Depth First Search

function dfs(adj)
{
  var s = 0;
  var V = adj.length;
  var visited = Array(V).fill(false);
  var ans = [];
  var stack = [];
  stack.push(s);

  while(stack.length != 0)
  {
    s = stack[stack.length - 1];
    stack.pop();

    if(visited[s] === false)
    {
      ans.push(s);
      visited[s] = true;
    }

    for(var i = 0; i != adj[s].length; ++i)
        if(visited[adj[s][i]] === false) stack.push(adj[s][i]);
  }
  return ans;
}