trie golf (#158)

* trie golf

* [auto-verifier] verify commit a2cd225

---------

Co-authored-by: GitHub <[email protected]>

Author: lrvideckis

.verify-helper/timestamps.remote.json

@@ -124,7 +124,7 @@
 "tests/library_checker_aizu_tests/strings/single_matching_bs.test.cpp": "2025-08-05 19:19:23 -0600",
 "tests/library_checker_aizu_tests/strings/suffix_array.test.cpp": "2025-08-06 09:59:41 -0600",
 "tests/library_checker_aizu_tests/strings/suffix_array_short.test.cpp": "2025-08-05 19:19:23 -0600",
-"tests/library_checker_aizu_tests/strings/trie.test.cpp": "2024-12-05 10:41:42 -0600",
+"tests/library_checker_aizu_tests/strings/trie.test.cpp": "2025-08-06 19:25:08 -0600",
 "tests/library_checker_aizu_tests/strings/wildcard_pattern_matching.test.cpp": "2025-08-05 19:19:23 -0600",
 "tests/library_checker_aizu_tests/trees/count_paths_per_length.test.cpp": "2025-08-06 13:48:07 -0600",
 "tests/library_checker_aizu_tests/trees/edge_cd_contour_range_query.test.cpp": "2025-08-06 19:02:15 -0600",

library/strings/trie.hpp

@@ -1,29 +1,25 @@
 #pragma once
 //! https://cp-algorithms.com/string/aho_corasick.html#construction-of-the-trie
-const int mn = 'A',
-          cnt_let = 26; // mn <= s[i] < mn + cnt_let
+const int mn = 'A';
 struct trie {
   struct node {
-    array<int, cnt_let> next;
-    int cnt_words = 0, par = -1;
-    char ch;
-    node(int par = -1, char ch = '#'): par(par), ch(ch) {
-      fill(all(next), -1);
-    }
+    array<int, 26> next;
+    bool end_of_word = 0;
+    node() { fill(all(next), -1); }
   };
-  vector<node> t;
+  deque<node> t;
   trie(): t(1) {}
   void insert(const string& s) {
     int v = 0;
     for (char ch : s) {
       int u = ch - mn;
       if (t[v].next[u] == -1) {
         t[v].next[u] = sz(t);
-        t.emplace_back(v, ch);
+        t.emplace_back();
       }
       v = t[v].next[u];
     }
-    t[v].cnt_words++;
+    t[v].end_of_word = 1;
   }
   int find(const string& s) {
     int v = 0;
@@ -32,6 +28,6 @@ struct trie {
       if (t[v].next[u] == -1) return 0;
       v = t[v].next[u];
     }
-    return t[v].cnt_words;
+    return t[v].end_of_word;
   }
 };