solution.js

/**
 * @param {number} n
 * @param {number[][]} edges
 * @return {number[]}
 */
var findMinHeightTrees = function (n, edges) {
    const depth = new Array(n).fill(0);
    const graph = new Array(n);
    const graph2 = new Array(n);
    for (let i = 0; i < n; i++) {
        graph[i] = [];
        graph2[i] = [];
    }
    for (let i = 0; i < edges.length; i++) {
        graph2[edges[i][0]].push(edges[i][1]);
        graph2[edges[i][1]].push(edges[i][0]);
    }
    const used = new Array(n).fill(false);
    used[0] = true;
    const stack = [
        0, ];
    while (stack.length) {
        const node = stack.pop();
        for (let i = 0; i < graph2[node].length; i++) {
            if (used[graph2[node][i]]) {
                continue;
            }
            graph[node].push(graph2[node][i]);
            stack.push(graph2[node][i]);
            used[graph2[node][i]] = true;
        }
    }

    function dfs (index) {
        if (graph[index].length === 0) {
            return 0;
        }

        const disList = graph[index].map((item) => dfs(item));

        const maxDis = Math.max(...disList) + 1;
        depth[index] = Math.max(maxDis, depth[index]);

        for (let i = 0; i < disList.length; i++) {
            let dis = 0;
            for (let j = 0; j < disList.length; j++) {
                if (i === j) {
                    continue;
                }
                dis = Math.max(dis, disList[j] + 1);
            }
            dfs2(graph[index][i], dis + 1);
        }
        return maxDis;
    }

    function dfs2 (index, dis) {
        depth[index] = Math.max(depth[index], dis++);
        for (let i = 0; i < graph[index].length; i++) {
            dfs2(graph[index][i], dis);
        }
    }

    dfs(0);

    const minDepth = Math.min(...depth);
    const result = [];
    for (let i = 0; i < n; i++) {
        if (depth[i] === minDepth) {
            result.push(i);
        }
    }
    return result;
};