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constexpr int MAX_CHAR = 256;
struct SuffixArray {
int n;
vector<int> SA, LCP;
vector<vector<int>> P;
SuffixArray(const string& s) : n(ssize(s)), SA(n), LCP(n),
P(__lg(2 * n - 1) + 1, vector<int>(n)) {
P[0].assign(begin(s), end(s));
iota(begin(SA), end(SA), 0);
ranges::sort(SA, {}, [&](int x) { return s[x]; });
vector<int> x(n);
for (int k = 1, c = 1; c < n; k++, c *= 2) {
iota(begin(x), end(x), n - c);
for (int ptr = c; int i : SA) if (i >= c) x[ptr++] = i - c;
vector<int> cnt(k == 1 ? MAX_CHAR : n);
for (int i : P[k-1]) cnt[i]++;
partial_sum(begin(cnt), end(cnt), begin(cnt));
for (int i : x | views::reverse) SA[--cnt[P[k-1][i]]] = i;
auto p = [&](int i) { return i < n ? P[k-1][i] : -1; };
for (int i = 1; i < n; i++) {
int a = SA[i-1], b = SA[i];
P[k][b] = P[k][a] + (p(a) != p(b) || p(a+c) != p(b+c));
}}
for (int i = 1; i < n; i++) LCP[i] = lcp(SA[i-1], SA[i]);
}
// x & y are text-indices, not SA-indices
int lcp(int x, int y) {
if (x == y) return n - x;
int res = 0;
for (int i = ssize(P) - 1; i >= 0 && max(x, y) + res < n; i--) {
if (P[i][x + res] == P[i][y + res]) res |= 1 << i;
}
return res;
}
};
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