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authormzuenni <michi.zuendorf@gmail.com>2023-03-28 13:25:59 +0200
committermzuenni <michi.zuendorf@gmail.com>2023-03-28 13:25:59 +0200
commitfe5fa1141efeb7454c763dbd2645fb4ff04487a3 (patch)
treef2197bb94ce80ab2fae886177dfa9b0bd11538ac /string/suffixAutomaton.cpp
parent3b91d2662310aee532cc84e1447824459671767e (diff)
merged
Diffstat (limited to 'string/suffixAutomaton.cpp')
-rw-r--r--string/suffixAutomaton.cpp42
1 files changed, 21 insertions, 21 deletions
diff --git a/string/suffixAutomaton.cpp b/string/suffixAutomaton.cpp
index 8b79822..4cc2a92 100644
--- a/string/suffixAutomaton.cpp
+++ b/string/suffixAutomaton.cpp
@@ -3,57 +3,57 @@ constexpr char OFFSET = 'a';
struct SuffixAutomaton {
struct State {
int len, link = -1;
- int nxt[ALPHABET_SIZE] = {}; // map if large Alphabet
+ array<int, ALPHABET_SIZE> next = {}; // map if large Alphabet
State(int l) : len(l) {}
};
- vector<State> st{0};
- int last = 0;
+ vector<State> st = {State(0)};
+ int cur = 0;
- SuffixAutomaton(const string &s) {
+ SuffixAutomaton(const string& s) {
st.reserve(2 * sz(s));
for (auto c : s) extend(c - OFFSET);
}
void extend(int c) {
- st.emplace_back(st[last].len + 1);
- int p = last, cur = last = sz(st) - 1;
- for (; p != -1 && !st[p].nxt[c]; p = st[p].link) {
- st[p].nxt[c] = cur;
+ int p = cur;
+ int cur = sz(st);
+ st.emplace_back(st[p].len + 1);
+ for (; p != -1 && !st[p].next[c]; p = st[p].link) {
+ st[p].next[c] = cur;
}
if (p == -1) st[cur].link = 0;
else {
- int q = st[p].nxt[c];
+ int q = st[p].next[c];
if (st[p].len + 1 == st[q].len) {
st[cur].link = q;
} else {
st.emplace_back(st[p].len + 1);
st.back().link = st[q].link;
- copy(all(st[q].nxt), st.back().nxt); // back.nxt=[q].nxt
- for (; p != -1 && st[p].nxt[c] == q; p = st[p].link) {
- st[p].nxt[c] = sz(st) - 1;
+ st.back().next = st[q].next;
+ for (; p != -1 && st[p].next[c] == q; p = st[p].link) {
+ st[p].next[c] = sz(st) - 1;
}
st[q].link = st[cur].link = sz(st) - 1;
- }}
- }
+ }}}
vector<int> calculateTerminals() {
vector<int> terminals;
- for (int p = last; p != -1; p = st[p].link) {
+ for (int p = cur; p != -1; p = st[p].link) {
terminals.push_back(p);
}
return terminals;
}
// Pair with start index (in t) and length of LCS.
- pair<int, int> longestCommonSubstring(const string &t) {
- int v = 0, l = 0, best = 0, bestpos = 0;
+ pair<int, int> longestCommonSubstring(const string& t) {
+ int v = 0, l = 0, best = 0, bestp = 0;
for (int i = 0; i < sz(t); i++) {
int c = t[i] - OFFSET;
- for (; v && !st[v].nxt[c]; v = st[v].link) l = st[v].len;
- if (st[v].nxt[c]) v = st[v].nxt[c], l++;
- if (l > best) best = l, bestpos = i;
+ for (; v && !st[v].next[c]; v = st[v].link) l = st[v].len;
+ if (st[v].next[c]) v = st[v].next[c], l++;
+ if (l > best) best = l, bestp = i;
}
- return {bestpos - best + 1, best};
+ return {bestp - best + 1, best};
}
};