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-rw-r--r--string/ahoCorasick.cpp52
1 files changed, 0 insertions, 52 deletions
diff --git a/string/ahoCorasick.cpp b/string/ahoCorasick.cpp
deleted file mode 100644
index eac312c..0000000
--- a/string/ahoCorasick.cpp
+++ /dev/null
@@ -1,52 +0,0 @@
-constexpr ll ALPHABET_SIZE = 26, OFFSET = 'a';
-struct AhoCorasick {
- struct vert {
- int suffix = 0, ch, cnt = 0;
- array<int, ALPHABET_SIZE> nxt = {};
-
- vert(int p, int c) : suffix(-p), ch(c) {}
- };
- vector<vert> aho = {{0, -1}};
-
- int addString(string &s) {
- int v = 0;
- for (auto c : s) {
- int idx = c - OFFSET;
- if (!aho[v].nxt[idx]) {
- aho[v].nxt[idx] = sz(aho);
- aho.emplace_back(v, idx);
- }
- v = aho[v].nxt[idx];
- }
- aho[v].cnt++;
- return v; // trie node index of pattern (pattern state)
- }
-
- int getSuffix(int v) {
- if (aho[v].suffix < 0) {
- aho[v].suffix = go(getSuffix(-aho[v].suffix), aho[v].ch);
- }
- return aho[v].suffix;
- }
-
- int go(int v, int idx) { // Root is v=0, idx is char - OFFSET
- if (aho[v].nxt[idx]) return aho[v].nxt[idx];
- else return v == 0 ? 0 : go(getSuffix(v), idx);
- }
-
- vector<vector<int>> adj;
- vector<ll> dp;
- void buildGraph() {
- adj.resize(sz(aho));
- dp.assign(sz(aho), 0);
- for (int i = 1; i < sz(aho); i++) {
- adj[getSuffix(i)].push_back(i);
- }}
-
- void dfs(int v = 0) { // dp on tree
- for (int u : adj[v]) {
- //dp[u] = dp[v] + aho[u].cnt; // pattern count
- dfs(u);
- dp[v] += dp[u]; // no of matches
- }}
-};