#include "string/string-search.hpp"
#pragma once #include "../atcoder/string.hpp" #include "../data-structure/sparse-table.hpp" template <typename Container> struct StringSearch { const Container& S; int N; vector<int> sa, la, invsa; SparseTable<int> sparse; StringSearch(const Container& _s) : S(_s), N(S.size()) { sa = atcoder::suffix_array(S); la = atcoder::lcp_array(S, sa); invsa.resize(N); for (int i = 0; i < N; i++) invsa[sa[i]] = i; sparse = SparseTable<int>{la}; } // lcp(s[i, N), s[j, N)) int lcp(int i, int j) { assert(0 <= min(i, j) and max(i, j) < N); if (i == j) return N - i; int x = min(invsa[i], invsa[j]); int y = max(invsa[i], invsa[j]); return sparse.query(x, y); } // lcp(s[a, b), s[c, d)) int lcp(int a, int b, int c, int d) { assert(0 <= a and a <= b and b <= N); assert(0 <= c and c <= d and d <= N); int l = lcp(a, c); return min({l, b - a, d - c}); } // lcp(s[a, b), s[c, d)) template <typename Int> int lcp(pair<Int, Int> p, pair<Int, Int> q) { return lcp(p.first, p.second, q.first, q.second); } // s[i, N) > s[j, N) : 1 // s[i, N) = s[j, N) : 0 // s[i, N) < s[j, N) : -1 int strcmp(int i, int j) { assert(0 <= min(i, j) and max(i, j) < N); if (i == j) return 0; return invsa[i] < invsa[j] ? -1 : 1; } // s[a, b) > s[c, d) : 1 // s[a, b) = s[c, d) : 0 // s[a, b) < s[c, d) : -1 int strcmp(int a, int b, int c, int d) { int l = lcp(a, b, c, d); return a + l == b ? (c + l == d ? 0 : -1) : c + l == d ? 1 : S[a + l] < S[c + l] ? -1 : 1; } // s[a, b) > s[c, d) : 1 // s[a, b) = s[c, d) : 0 // s[a, b) < s[c, d) : -1 template <typename Int> int strcmp(pair<Int, Int> p, pair<Int, Int> q) { return strcmp(p.first, p.second, q.first, q.second); } };
#line 2 "string/string-search.hpp" #line 1 "atcoder/string.hpp" #include <algorithm> #include <cassert> #include <numeric> #include <string> #include <vector> namespace atcoder { namespace internal { std::vector<int> sa_naive(const std::vector<int>& s) { int n = int(s.size()); std::vector<int> sa(n); std::iota(sa.begin(), sa.end(), 0); std::sort(sa.begin(), sa.end(), [&](int l, int r) { if (l == r) return false; while (l < n && r < n) { if (s[l] != s[r]) return s[l] < s[r]; l++; r++; } return l == n; }); return sa; } std::vector<int> sa_doubling(const std::vector<int>& s) { int n = int(s.size()); std::vector<int> sa(n), rnk = s, tmp(n); std::iota(sa.begin(), sa.end(), 0); for (int k = 1; k < n; k *= 2) { auto cmp = [&](int x, int y) { if (rnk[x] != rnk[y]) return rnk[x] < rnk[y]; int rx = x + k < n ? rnk[x + k] : -1; int ry = y + k < n ? rnk[y + k] : -1; return rx < ry; }; std::sort(sa.begin(), sa.end(), cmp); tmp[sa[0]] = 0; for (int i = 1; i < n; i++) { tmp[sa[i]] = tmp[sa[i - 1]] + (cmp(sa[i - 1], sa[i]) ? 1 : 0); } std::swap(tmp, rnk); } return sa; } // SA-IS, linear-time suffix array construction // Reference: // G. Nong, S. Zhang, and W. H. Chan, // Two Efficient Algorithms for Linear Time Suffix Array Construction template <int THRESHOLD_NAIVE = 10, int THRESHOLD_DOUBLING = 40> std::vector<int> sa_is(const std::vector<int>& s, int upper) { int n = int(s.size()); if (n == 0) return {}; if (n == 1) return {0}; if (n == 2) { if (s[0] < s[1]) { return {0, 1}; } else { return {1, 0}; } } if (n < THRESHOLD_NAIVE) { return sa_naive(s); } if (n < THRESHOLD_DOUBLING) { return sa_doubling(s); } std::vector<int> sa(n); std::vector<bool> ls(n); for (int i = n - 2; i >= 0; i--) { ls[i] = (s[i] == s[i + 1]) ? ls[i + 1] : (s[i] < s[i + 1]); } std::vector<int> sum_l(upper + 1), sum_s(upper + 1); for (int i = 0; i < n; i++) { if (!ls[i]) { sum_s[s[i]]++; } else { sum_l[s[i] + 1]++; } } for (int i = 0; i <= upper; i++) { sum_s[i] += sum_l[i]; if (i < upper) sum_l[i + 1] += sum_s[i]; } auto induce = [&](const std::vector<int>& lms) { std::fill(sa.begin(), sa.end(), -1); std::vector<int> buf(upper + 1); std::copy(sum_s.begin(), sum_s.end(), buf.begin()); for (auto d : lms) { if (d == n) continue; sa[buf[s[d]]++] = d; } std::copy(sum_l.begin(), sum_l.end(), buf.begin()); sa[buf[s[n - 1]]++] = n - 1; for (int i = 0; i < n; i++) { int v = sa[i]; if (v >= 1 && !ls[v - 1]) { sa[buf[s[v - 1]]++] = v - 1; } } std::copy(sum_l.begin(), sum_l.end(), buf.begin()); for (int i = n - 1; i >= 0; i--) { int v = sa[i]; if (v >= 1 && ls[v - 1]) { sa[--buf[s[v - 1] + 1]] = v - 1; } } }; std::vector<int> lms_map(n + 1, -1); int m = 0; for (int i = 1; i < n; i++) { if (!ls[i - 1] && ls[i]) { lms_map[i] = m++; } } std::vector<int> lms; lms.reserve(m); for (int i = 1; i < n; i++) { if (!ls[i - 1] && ls[i]) { lms.push_back(i); } } induce(lms); if (m) { std::vector<int> sorted_lms; sorted_lms.reserve(m); for (int v : sa) { if (lms_map[v] != -1) sorted_lms.push_back(v); } std::vector<int> rec_s(m); int rec_upper = 0; rec_s[lms_map[sorted_lms[0]]] = 0; for (int i = 1; i < m; i++) { int l = sorted_lms[i - 1], r = sorted_lms[i]; int end_l = (lms_map[l] + 1 < m) ? lms[lms_map[l] + 1] : n; int end_r = (lms_map[r] + 1 < m) ? lms[lms_map[r] + 1] : n; bool same = true; if (end_l - l != end_r - r) { same = false; } else { while (l < end_l) { if (s[l] != s[r]) { break; } l++; r++; } if (l == n || s[l] != s[r]) same = false; } if (!same) rec_upper++; rec_s[lms_map[sorted_lms[i]]] = rec_upper; } auto rec_sa = sa_is<THRESHOLD_NAIVE, THRESHOLD_DOUBLING>(rec_s, rec_upper); for (int i = 0; i < m; i++) { sorted_lms[i] = lms[rec_sa[i]]; } induce(sorted_lms); } return sa; } } // namespace internal std::vector<int> suffix_array(const std::vector<int>& s, int upper) { assert(0 <= upper); for (int d : s) { assert(0 <= d && d <= upper); } auto sa = internal::sa_is(s, upper); return sa; } template <class T> std::vector<int> suffix_array(const std::vector<T>& s) { int n = int(s.size()); std::vector<int> idx(n); iota(idx.begin(), idx.end(), 0); sort(idx.begin(), idx.end(), [&](int l, int r) { return s[l] < s[r]; }); std::vector<int> s2(n); int now = 0; for (int i = 0; i < n; i++) { if (i && s[idx[i - 1]] != s[idx[i]]) now++; s2[idx[i]] = now; } return internal::sa_is(s2, now); } std::vector<int> suffix_array(const std::string& s) { int n = int(s.size()); std::vector<int> s2(n); for (int i = 0; i < n; i++) { s2[i] = s[i]; } return internal::sa_is(s2, 255); } // Reference: // T. Kasai, G. Lee, H. Arimura, S. Arikawa, and K. Park, // Linear-Time Longest-Common-Prefix Computation in Suffix Arrays and Its // Applications template <class T> std::vector<int> lcp_array(const std::vector<T>& s, const std::vector<int>& sa) { int n = int(s.size()); assert(n >= 1); std::vector<int> rnk(n); for (int i = 0; i < n; i++) { rnk[sa[i]] = i; } std::vector<int> lcp(n - 1); int h = 0; for (int i = 0; i < n; i++) { if (h > 0) h--; if (rnk[i] == 0) continue; int j = sa[rnk[i] - 1]; for (; j + h < n && i + h < n; h++) { if (s[j + h] != s[i + h]) break; } lcp[rnk[i] - 1] = h; } return lcp; } std::vector<int> lcp_array(const std::string& s, const std::vector<int>& sa) { int n = int(s.size()); std::vector<int> s2(n); for (int i = 0; i < n; i++) { s2[i] = s[i]; } return lcp_array(s2, sa); } // Reference: // D. Gusfield, // Algorithms on Strings, Trees, and Sequences: Computer Science and // Computational Biology template <class T> std::vector<int> z_algorithm(const std::vector<T>& s) { int n = int(s.size()); if (n == 0) return {}; std::vector<int> z(n); z[0] = 0; for (int i = 1, j = 0; i < n; i++) { int& k = z[i]; k = (j + z[j] <= i) ? 0 : std::min(j + z[j] - i, z[i - j]); while (i + k < n && s[k] == s[i + k]) k++; if (j + z[j] < i + z[i]) j = i; } z[0] = n; return z; } std::vector<int> z_algorithm(const std::string& s) { int n = int(s.size()); std::vector<int> s2(n); for (int i = 0; i < n; i++) { s2[i] = s[i]; } return z_algorithm(s2); } } // namespace atcoder #line 2 "data-structure/sparse-table.hpp" #line 4 "data-structure/sparse-table.hpp" #include <limits> #line 6 "data-structure/sparse-table.hpp" using namespace std; template <typename T> struct SparseTable { inline static constexpr T INF = numeric_limits<T>::max() / 2; int N; vector<vector<T> > table; T f(T a, T b) { return min(a, b); } SparseTable() {} SparseTable(const vector<T> &v) : N(v.size()) { int b = 1; while ((1 << b) <= N) ++b; table.push_back(v); for (int i = 1; i < b; i++) { table.push_back(vector<T>(N, INF)); for (int j = 0; j + (1 << i) <= N; j++) { table[i][j] = f(table[i - 1][j], table[i - 1][j + (1 << (i - 1))]); } } } // [l, r) T query(int l, int r) { assert(0 <= l and l <= r and r <= N); if (l == r) return INF; int b = 31 - __builtin_clz(r - l); return f(table[b][l], table[b][r - (1 << b)]); } }; /** * @brief Sparse Table */ #line 5 "string/string-search.hpp" template <typename Container> struct StringSearch { const Container& S; int N; vector<int> sa, la, invsa; SparseTable<int> sparse; StringSearch(const Container& _s) : S(_s), N(S.size()) { sa = atcoder::suffix_array(S); la = atcoder::lcp_array(S, sa); invsa.resize(N); for (int i = 0; i < N; i++) invsa[sa[i]] = i; sparse = SparseTable<int>{la}; } // lcp(s[i, N), s[j, N)) int lcp(int i, int j) { assert(0 <= min(i, j) and max(i, j) < N); if (i == j) return N - i; int x = min(invsa[i], invsa[j]); int y = max(invsa[i], invsa[j]); return sparse.query(x, y); } // lcp(s[a, b), s[c, d)) int lcp(int a, int b, int c, int d) { assert(0 <= a and a <= b and b <= N); assert(0 <= c and c <= d and d <= N); int l = lcp(a, c); return min({l, b - a, d - c}); } // lcp(s[a, b), s[c, d)) template <typename Int> int lcp(pair<Int, Int> p, pair<Int, Int> q) { return lcp(p.first, p.second, q.first, q.second); } // s[i, N) > s[j, N) : 1 // s[i, N) = s[j, N) : 0 // s[i, N) < s[j, N) : -1 int strcmp(int i, int j) { assert(0 <= min(i, j) and max(i, j) < N); if (i == j) return 0; return invsa[i] < invsa[j] ? -1 : 1; } // s[a, b) > s[c, d) : 1 // s[a, b) = s[c, d) : 0 // s[a, b) < s[c, d) : -1 int strcmp(int a, int b, int c, int d) { int l = lcp(a, b, c, d); return a + l == b ? (c + l == d ? 0 : -1) : c + l == d ? 1 : S[a + l] < S[c + l] ? -1 : 1; } // s[a, b) > s[c, d) : 1 // s[a, b) = s[c, d) : 0 // s[a, b) < s[c, d) : -1 template <typename Int> int strcmp(pair<Int, Int> p, pair<Int, Int> q) { return strcmp(p.first, p.second, q.first, q.second); } };