Create 472-concatenated-words.js

Author: everthis

472-concatenated-words.js

@@ -0,0 +1,27 @@
+/**
+ * @param {string[]} words
+ * @return {string[]}
+ */
+const findAllConcatenatedWordsInADict = function(words) {
+  let res = []
+  if (words === null || words.length == 0) return res
+  let set = new Set(words)
+  for (let word of words) {
+    set.delete(word)
+    if (dfs(word, set, '')) res.push(word)
+    set.add(word)
+  }
+  return res
+}
+
+function dfs(word, set, prev) {
+  if (prev != '') set.add(prev)
+  if (set.has(word)) return true
+  for (let i = 1; i <= word.length; i++) {
+    const prefix = word.substring(0, i)
+    if (set.has(prefix) && dfs(word.substring(i), set, prev + prefix)) {
+      return true
+    }
+  }
+  return false
+}