class StringAlgorithm { private static int[] saNaive(int[] s) { int n = s.length; Integer[] _sa = new Integer[n]; for (int i = 0; i < n; i++) { _sa[i] = i; } java.util.Arrays.sort(_sa, (l, r) -> { while (l < n && r < n) { if (s[l] != s[r]) return s[l] - s[r]; l++; r++; } return -(l - r); }); int[] sa = new int[n]; for (int i = 0; i < n; i++) { sa[i] = _sa[i]; } return sa; } private static int[] saDoubling(int[] s) { int n = s.length; Integer[] _sa = new Integer[n]; for (int i = 0; i < n; i++) { _sa[i] = i; } int[] rnk = s; int[] tmp = new int[n]; for (int k = 1; k < n; k *= 2) { final int _k = k; final int[] _rnk = rnk; java.util.Comparator cmp = (x, 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; }; java.util.Arrays.sort(_sa, cmp); tmp[_sa[0]] = 0; for (int i = 1; i < n; i++) { tmp[_sa[i]] = tmp[_sa[i - 1]] + (cmp.compare(_sa[i - 1], _sa[i]) < 0 ? 1 : 0); } int[] buf = tmp; tmp = rnk; rnk = buf; } int[] sa = new int[n]; for (int i = 0; i < n; i++) { sa[i] = _sa[i]; } return sa; } private static final int THRESHOLD_NAIVE = 10; private static final int THRESHOLD_DOUBLING = 40; private static int[] sais(int[] s, int upper) { int n = s.length; if (n == 0) return new int[0]; if (n == 1) return new int[]{0}; if (n == 2) { if (s[0] < s[1]) { return new int[]{0, 1}; } else { return new int[]{1, 0}; } } if (n < THRESHOLD_NAIVE) { return saNaive(s); } if (n < THRESHOLD_DOUBLING) { return saDoubling(s); } int[] sa = new int[n]; boolean[] ls = new boolean[n]; for (int i = n - 2; i >= 0; i--) { ls[i] = s[i] == s[i + 1] ? ls[i + 1] : s[i] < s[i + 1]; } int[] sumL = new int[upper + 1]; int[] sumS = new int[upper + 1]; for (int i = 0; i < n; i++) { if (ls[i]) { sumL[s[i] + 1]++; } else { sumS[s[i]]++; } } for (int i = 0; i <= upper; i++) { sumS[i] += sumL[i]; if (i < upper) sumL[i + 1] += sumS[i]; } java.util.function.Consumer induce = lms -> { java.util.Arrays.fill(sa, -1); int[] buf = new int[upper + 1]; System.arraycopy(sumS, 0, buf, 0, upper + 1); for (int d : lms) { if (d == n) continue; sa[buf[s[d]]++] = d; } System.arraycopy(sumL, 0, buf, 0, upper + 1); 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; } } System.arraycopy(sumL, 0, buf, 0, upper + 1); 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; } } }; int[] lmsMap = new int[n + 1]; java.util.Arrays.fill(lmsMap, -1); int m = 0; for (int i = 1; i < n; i++) { if (!ls[i - 1] && ls[i]) { lmsMap[i] = m++; } } int[] lms = new int[m]; { int p = 0; for (int i = 1; i < n; i++) { if (!ls[i - 1] && ls[i]) { lms[p++] = i; } } } induce.accept(lms); if (m > 0) { int[] sortedLms = new int[m]; { int p = 0; for (int v : sa) { if (lmsMap[v] != -1) { sortedLms[p++] = v; } } } int[] recS = new int[m]; int recUpper = 0; recS[lmsMap[sortedLms[0]]] = 0; for (int i = 1; i < m; i++) { int l = sortedLms[i - 1], r = sortedLms[i]; int endL = (lmsMap[l] + 1 < m) ? lms[lmsMap[l] + 1] : n; int endR = (lmsMap[r] + 1 < m) ? lms[lmsMap[r] + 1] : n; boolean same = true; if (endL - l != endR - r) { same = false; } else { while (l < endL && s[l] == s[r]) { l++; r++; } if (l == n || s[l] != s[r]) same = false; } if (!same) { recUpper++; } recS[lmsMap[sortedLms[i]]] = recUpper; } int[] recSA = sais(recS, recUpper); for (int i = 0; i < m; i++) { sortedLms[i] = lms[recSA[i]]; } induce.accept(sortedLms); } return sa; } public static int[] suffixArray(int[] s, int upper) { assert (0 <= upper); for (int d : s) { assert (0 <= d && d <= upper); } return sais(s, upper); } public static int[] suffixArray(int[] s) { int n = s.length; Integer[] idx = new Integer[n]; for (int i = 0; i < n; i++) { idx[i] = i; } java.util.Arrays.sort(idx, (l, r) -> s[l] - s[r]); int[] s2 = new int[n]; int now = 0; for (int i = 0; i < n; i++) { if (i > 0 && s[idx[i - 1]] != s[idx[i]]) { now++; } s2[idx[i]] = now; } return sais(s2, now); } public static int[] suffixArray(char[] s) { int n = s.length; int[] s2 = new int[n]; for (int i = 0; i < n; i++) { s2[i] = s[i]; } return sais(s2, 255); } public static int[] suffixArray(java.lang.String s) { return suffixArray(s.toCharArray()); } public static int[] lcpArray(int[] s, int[] sa) { int n = s.length; assert (n >= 1); int[] rnk = new int[n]; for (int i = 0; i < n; i++) { rnk[sa[i]] = i; } int[] lcp = new int[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; } public static int[] lcpArray(char[] s, int[] sa) { int n = s.length; int[] s2 = new int[n]; for (int i = 0; i < n; i++) { s2[i] = s[i]; } return lcpArray(s2, sa); } public static int[] lcpArray(java.lang.String s, int[] sa) { return lcpArray(s.toCharArray(), sa); } public static int[] zAlgorithm(int[] s) { int n = s.length; if (n == 0) return new int[0]; int[] z = new int[n]; for (int i = 1, j = 0; i < n; i++) { int k = j + z[j] <= i ? 0 : Math.min(j + z[j] - i, z[i - j]); while (i + k < n && s[k] == s[i + k]) k++; z[i] = k; if (j + z[j] < i + z[i]) j = i; } z[0] = n; return z; } public static int[] zAlgorithm(char[] s) { int n = s.length; if (n == 0) return new int[0]; int[] z = new int[n]; for (int i = 1, j = 0; i < n; i++) { int k = j + z[j] <= i ? 0 : Math.min(j + z[j] - i, z[i - j]); while (i + k < n && s[k] == s[i + k]) k++; z[i] = k; if (j + z[j] < i + z[i]) j = i; } z[0] = n; return z; } public static int[] zAlgorithm(String s) { return zAlgorithm(s.toCharArray()); } }