Function alienOrder

javascript/0269-alien-dictionary.js:7–16

(words)

 * @return {string}
 */
var alienOrder = function (words) {
    const { graph, frequencyMap, queue, buffer } = buildGraph(words);

    if (!canBuildGraph(words, graph, frequencyMap)) return '';

    queueSources(queue, frequencyMap);
    bfs(queue, frequencyMap, graph, buffer);

    return frequencyMap.size <= buffer.length ? buffer.join('') : '';
};

var initGraph = () => ({
    graph: new Map(),