sam_code

802I_本质不同字串出现次数平方和

NAME MeIoN_is_UMP45() {string s;std::cin >> s;const int n = s.length();SAM sam(n << 1);vector<int> sz(n << 1);for (int pla = 0; const char c : s) {pla = sam.ext(pla, c - 'a');sz[pla] = 1;}vector<vector<int>> v(n << 1);for (int i = 1; i < sam.size(); ++i) {v[sam[i].link].emplace_back(i);}meion dfs = [&](meion &&se, int n) -> void {for (const int i : v[n]) {se(se, i);sz[n] += sz[i];}};dfs(dfs, 0);ll ans = 0;for (int i = 1; i < sam.size(); ++i) {ans += 1ll * sz[i] * sz[i] * (sam[i].len - sam[sam[i].link].len);}std::cout << ans << '\n';
}

多个串的最长公共字串

NAME MeIoN_is_UMP45() {string s, ss;std::cin >> s;const int n = s.length();array<SAM, 11> sam;int tot = 0;while (std::cin >> ss) {for (int pla = 0; const char c : ss) {pla = sam[tot].ext(pla, c - 'a');}++tot;}vector<int> slen(n, inf<int>);for (int i = 0; i < tot; ++i) {int pla = 0, plen = 0;meion &sa = sam[i];for (int i = 0; const char c : s) { if (sa[pla][c - 'a'] == -1) {while (pla != 0 and sa[pla][c - 'a'] == -1) {pla = sa[pla].link;}plen = sa[pla].len;}if (sa[pla][c - 'a'] != -1) {pla = sa[pla][c - 'a'];++plen;}chmin(slen[i++], plen);}}std::cout << qmax(slen) << '\n';
}

两个子串相同的方案数

NAME MeIoN_is_UMP45() {string s, ss;std::cin >> s >> ss;const int n = s.length(), m = ss.length();SAM sam(n + m << 1);vector<int> sz(n + m << 1), szz(sz);// 建立广义sam 暴算for (int pla = 0; char c : s) {pla = sam.ext(pla, c - 'a');sz[pla] = 1;}for (int pla = 0; char c : ss) {pla = sam.ext(pla, c - 'a');szz[pla] = 1;}vector<vector<int>> v(sam.size());for (int i = 1; i < sam.size(); ++i) {v[sam[i].link].emplace_back(i);}ll ans = 0;meion dfs = [&](meion &&se, int n) -> void {for (int i : v[n]) {se(se, i);sz[n] += sz[i];szz[n] += szz[i];ans += 1ll * sz[i] * szz[i] * (sam[i].len - sam[n].len);}};dfs(dfs, 0);std::cout << ans << '\n';
}

P_2408_不同子串个数

NAME MeIoN_is_UMP45() {int n;string s;std::cin >> n >> s;SAM sam(n << 1);for (int pla = 0; const char c : s) {pla = sam.ext(pla, c - 'a');}ll ans = 0;// 每个pos存着所有结束pos相同的子串集合, len为最长字串, link_pos的最长字串length为// pos的 最短字串 的length - 1for (int i = 1; i < sam.size(); ++i) {// 最长len - 最短len + 1 为串数量ans += sam[i].len - sam[sam[i].link].len;}std::cout << ans << '\n';
}

P_3804_模板_后缀自动机_SAM

NAME MeIoN_is_UMP45() {string s;std::cin >> s;const int n = s.length();SAM sam(n << 1);vector<int> sz(n << 1);for (int pla = 0; const char c : s) {pla = sam.ext(pla, c - 'a');sz[pla] = 1;}vector<vector<int>> v(sam.size());for (int i = 1; i < sam.size(); ++i) {v[sam[i].link].emplace_back(i);}ll ans = 0;meion dfs = [&](meion &&se, int n) -> void {for (const int i : v[n]) {se(se, i);sz[n] += sz[i];}if (sz[n] > 1) chmax(ans, 1ll * sz[n] * sam[n].len);};dfs(dfs, 0);std::cout << ans << '\n';
}

P_3975_TJOI_2015_弦论

NAME MeIoN_is_UMP45() {string s;int t, k;std::cin >> s >> t >> k;const int n = s.length();SAM sam;vector<int> sz(n << 1);for (int pla = 0; const char c : s) {pla = sam.ext(pla, c - 'a');sz[pla] = 1;}vector<vector<int>> v(n << 1);for (int i = 1; i < sam.size(); ++i) {v[sam[i].link].emplace_back(i);}meion dfs = [&](meion &&se, int n) -> void {for (int i : v[n]) {se(se, i);sz[n] += sz[i];}if (not t) sz[n] = 1;};dfs(dfs, 0);sz[0] = 0;vector<uint8_t> vis(n << 1);vector<ll> dp(n << 1);meion go = [&](meion &&se, int n) -> void {if (vis[n]) iroha;vis[n] = 1;dp[n] = sz[n];for (int i = 0, x; i < 26; ++i) {x = sam[n][i];if (x == -1) continue;se(se, x);dp[n] += dp[x];}};go(go, 0);int pla = 0;if (dp[pla] < k) iroha std::cout << "-1\n", void();string ans;while (k > 0) {for (int i = 0, x; i < 26; ++i) {x = sam[pla][i];if (x == -1) continue;if (k > dp[x]) {k -= dp[x];} else {pla = x;k -= sz[pla];ans += char('a' + i);break;}}}std::cout << ans << '\n';
}

s[l, r]与t的最长公共字串(Olog_/_O1)

NAME MeIoN_is_UMP45() {string s, t;int q;std::cin >> s >> t >> q;SAM sam;meion [sz, v] = sam.build(t);const int n = s.length();vector<int> slen(n, inf<int>);for (int i = 0, pla = 0, plen = 0; const char c : s) {if (sam[pla][c - 'a'] == -1) {while (pla != 0 and sam[pla][c - 'a'] == -1) {pla = sam[pla].link;}plen = sam[pla].len;}if (sam[pla][c - 'a'] != -1) {pla = sam[pla][c - 'a'];++plen;}chmin(slen[i++], plen);}sqrt_tree<monoid_max<int>> table(slen);for (int i = 0, l, r, m, S; i < q; ++i) {std::cin >> l >> r, --l;m = binary_search([&](int x) -> bool {if (x == r) iroha true;iroha x - slen[x] + 1 > l - 1;}, r, l - 1);if (m == r) std::cout << r - l << '\n';else std::cout << std::max(table.prod(m, r), m - l) << '\n';}
}

s的循环在t的几个字串中出现

NAME MeIoN_is_UMP45() {string s;std::cin >> s;SAM sam;meion [sz, v] = sam.build(s);static bitset<2000001> vis;int q;std::cin >> q;for (int i = 0; i < q; ++i) {std::cin >> s;vis.reset();const int n = s.length();int slen = 0, pla = 0;for (const char c : s) {while (pla != 0 and sam[pla][c - 'a'] == -1) {pla = sam[pla].link;slen = sam[pla].len;}if (sam[pla][c - 'a'] != -1) {pla = sam[pla][c - 'a'];++slen;}}ll ans = 0;for (int i = 0; i < n; ++i) {if (slen == n) {if (not vis[pla]) {ans += sz[pla];}vis[pla] = 1;--slen;if (slen == sam[sam[pla].link].len) {pla = sam[pla].link;}}while (pla != 0 and sam[pla][s[i] - 'a'] == -1) {pla = sam[pla].link;slen = sam[pla].len;}if (sam[pla][s[i] - 'a'] != -1) {pla = sam[pla][s[i] - 'a'];++slen;}}std::cout << ans << '\n';}
}