Update 472-concatenated-words.js

Author: everthis

472-concatenated-words.js

@@ -1,3 +1,40 @@
+/**
+ * @param {string[]} words
+ * @return {string[]}
+ */
+
+const findAllConcatenatedWordsInADict = function (words) {
+  const set = new Set(words)
+  const res = []
+  const map = new Map()
+  for (let w of words) {
+    if (w.length < 2) continue
+    if (dfs(w, set, map, 0)) res.push(w)
+  }
+  return res
+
+  function dfs(word, set, map, pos) {
+    if (pos > 0 && map.get(word)) return map.get(word)
+    if (pos > 0 && set.has(word)) {
+      map.set(word, true)
+      return map.get(word)
+    }
+    for (let i = 1; i < word.length; i++) {
+      const left = word.slice(0, i)
+      const right = word.slice(i)
+      if (set.has(right) && dfs(left, set, map, pos + 1)) {
+        map.set(word, true)
+        return map.get(word)
+      }
+    }
+
+    map.set(word, false)
+    return false
+  }
+}
+
+// another
+
 /**
  * @param {string[]} words
  * @return {string[]}