Create 1065-index-pairs-of-a-string.js

Author: everthis

1065-index-pairs-of-a-string.js

@@ -0,0 +1,41 @@
+/**
+ * @param {string} text
+ * @param {string[]} words
+ * @return {number[][]}
+ */
+const indexPairs = function(text, words) {
+  const res = [], trie = buildTrie(words)
+  const n = text.length
+  for(let i = 0; i < n; i++) {
+    let node = trie
+    for(let j = i; j < n; j++) {
+      if(node.children[text[j]] == null) break
+      node = node.children[text[j]]
+      if(node.isWord) res.push([i, j])
+    }
+  }
+
+  return res
+};
+
+function buildTrie(words) {
+  const root = new Trie()
+  
+  for(let word of words) {
+    let node = root
+    for(let c of word) {
+      if(node.children[c] == null) node.children[c] = new Trie()
+      node = node.children[c]
+    }
+    node.isWord = true
+  }
+
+  return root
+}
+
+class Trie {
+  constructor() {
+    this.children = {}
+    this.isWord = false
+  }
+}