#include <bits/stdc++.h> using namespace std; typedef vector<vector<short>> Array; typedef vector<short> ArrayRow; typedef pair<int,int> Pos; typedef pair<int,int> OrdPos; /* typedef vector<vector<pair<int,short>>> LayerJumps; */ //int layer_size, layers_cnt; struct Query { Pos a, b; int idx; int answer; Query(): answer(-1) {}; Query(Pos _a, Pos _b, int _idx): a(_a), b(_b), idx(_idx), answer(-1) {}; }; string A, B; int n, m; bool inside(const OrdPos& p) { return (p.first >= 0) && (p.second >= 0) && (p.first < n) && (p.second < m); } inline Pos from_ord_pos(const OrdPos& p) { int row = p.first + p.second; int which = (row < m) ? (p.first) : (p.first - row + (m-1)); return make_pair(row, which); } inline OrdPos to_ord_pos(const Pos& p) { int y = (p.first < m) ? (p.second) : (p.first + p.second - (m-1)); int x = p.first - y; return make_pair(y, x); } /* inline int row_size(int r) { return min(min(n, m), min(r, n + m - r)) + 1; } inline int row_to_layer(int r) { return r / layer_size; } inline int layer_to_row(int l) { return l * layer_size; } inline int next_layer_splitter(int r) { return layer_to_row(row_to_layer(r + layer_size - 1)); } inline int prev_layer_splitter(int r) { return layer_to_row(row_to_layer(r)); } inline void initialize(vector<vector<int>>& v, int sz) { v.resize(sz, vector<int>()); for (int i = 0; i < sz; i++) v[i].resize(sz - i); } */ inline short safe_get(const Array& dp, int i, int j) { if ((i < 0) || (j < 0)) return 0; return dp[i][j]; } inline short smax(short a, short b) { return (a > b) ? a : b; } inline short smax(short a, short b, short c) { return smax(smax(a, b), c); } inline char get_char(const string& s, int p, char fail_char) { if ((p >= 0) && (p < s.length())) return s[p]; return fail_char; } /* inline int is_pos_good(const Pos& p) { OrdPos q = to_ord_pos(p); return get_char(A, q.first, '$') == get_char(B, q.second, '#'); } inline int is_pos_good(int layer, int which) { return is_pos_good(make_pair(layer_to_row(layer), which)); } */ int naive_dp(const Pos& a, const Pos& b) { OrdPos ap = to_ord_pos(a); OrdPos bp = to_ord_pos(b); int height = bp.first - ap.first + 1; int width = bp.second - ap.second + 1; Array dp(height, ArrayRow(width, 0)); for (int i = 0; i < height; i++) for (int j = 0; j < width; j++) { if (get_char(A, ap.first + i, '$') == get_char(B, ap.second + j, '#')) dp[i][j] = smax(dp[i][j], safe_get(dp, i-1, j-1) + 1); else dp[i][j] = smax(dp[i][j], safe_get(dp, i-1, j), safe_get(dp, i, j-1)); } return dp[height-1][width-1]; } vector<Query> query; /* vector<vector<int>> query_groups; vector<pair<int,short>> rightdown_triangle_dp(const Pos& x, bool go_next = false) { OrdPos p = to_ord_pos(x); int sz = next_layer_splitter(x.first + (int)go_next) - x.first + 1; Array dp(sz, ArrayRow(sz, -1)); for (int i = 0; i < sz; i++) for (int j = 0; i+j < sz; j++) { if (get_char(A, p.first + i, '$') == get_char(B, p.second + j, '#')) dp[i][j] = smax(dp[i][j], safe_get(dp, i-1, j-1) + 1); else dp[i][j] = smax(dp[i][j], safe_get(dp, i-1, j), safe_get(dp, i, j-1)); } vector<pair<int,short>> results; for (int i = 0; i < sz; i++) { OrdPos q = make_pair(p.first + i, p.second + (sz - 1 - i)); if (!inside(q)) continue; Pos rq = from_ord_pos(q); results.push_back(make_pair(rq.second, dp[i][sz-1-i])); } return results; } vector<pair<int,short>> leftup_triangle_dp(const Pos& x) { OrdPos p = to_ord_pos(x); int sz = x.first - prev_layer_splitter(x.first) + 1; Array dp(sz, ArrayRow(sz, -1)); for (int i = 0; i < sz; i++) for (int j = 0; i+j < sz; j++) { if (get_char(A, p.first - i, '$') == get_char(B, p.second - j, '#')) dp[i][j] = smax(dp[i][j], safe_get(dp, i-1, j-1) + 1); else dp[i][j] = smax(dp[i][j], safe_get(dp, i-1, j), safe_get(dp, i, j-1)); } vector<pair<int,short>> results; for (int i = 0; i < sz; i++) { OrdPos q = make_pair(p.first - i, p.second - (sz - 1 - i)); if (!inside(q)) continue; Pos rq = from_ord_pos(q); results.push_back(make_pair(rq.second, dp[i][sz-1-i])); } return results; } vector<LayerJumps> jump_next_layer; vector<LayerJumps> jump_few_layers; vector<LayerJumps> X_jump_few_layers; LayerJumps merge_jumps(int lid, int ldiff, const LayerJumps& jumps1, const LayerJumps& jumps2) { int mid_v, cost_st_mid, fn_v, cost_mid_fn; LayerJumps result(jumps1.size()); for (int st_v = 0; st_v < jumps1.size(); st_v++) { unordered_map<int,short> st_result; for (const auto& mid_jump : jumps1[st_v]) { mid_v = mid_jump.first; if (jumps2.empty()) break; if (mid_v >= jumps2.size()) continue; cost_st_mid = mid_jump.second - is_pos_good(lid + ldiff, mid_v); for (const auto& fn_jump : jumps2[mid_v]) { fn_v = fn_jump.first; cost_mid_fn = fn_jump.second; cerr << "jump from " << lid << " " << st_v << " through " << lid + ldiff << " " << mid_v << " to end in " << lid + ldiff + 1 << " " << fn_v << " for costs " << cost_st_mid + is_pos_good(lid + ldiff, mid_v) << " and " << cost_mid_fn << " (" << is_pos_good(lid + ldiff, mid_v) << ") = " << cost_st_mid + cost_mid_fn << "\n"; if ((st_result.count(fn_v) == 0) || (st_result[fn_v] < cost_st_mid + cost_mid_fn)) { st_result[fn_v] = cost_st_mid + cost_mid_fn; } } } result[st_v] = vector<pair<int,short>>(st_result.begin(), st_result.end()); } return result; } int merge3(int lid, int ldiff, const vector<pair<int,short>>& st_jumps, const LayerJumps& mid_jumps, const vector<pair<int,short>>& jumps_fn) { unordered_map<int,short> st_jumps_lookup(st_jumps.begin(), st_jumps.end()); unordered_map<int,short> jumps_fn_lookup(jumps_fn.begin(), jumps_fn.end()); int best = 0; int right_mid_v, left_right_mid_cost, st_mid_cost, mid_fn_cost, cost; for (int left_mid_v = 0; left_mid_v < mid_jumps.size(); left_mid_v++) { if (st_jumps_lookup.count(left_mid_v) == 0) continue; st_mid_cost = st_jumps_lookup.at(left_mid_v) - is_pos_good(lid, left_mid_v); if ((mid_jumps.empty()) || (left_mid_v >= mid_jumps.size())) continue; for (const auto& right_mid_jump : mid_jumps[left_mid_v]) { if (jumps_fn_lookup.count(right_mid_v) == 0) continue; right_mid_v = right_mid_jump.first; left_right_mid_cost = right_mid_jump.second - is_pos_good(lid + ldiff, right_mid_v); mid_fn_cost = jumps_fn_lookup.at(right_mid_v); cost = st_mid_cost + left_right_mid_cost + mid_fn_cost; cerr << "go through big jump " << left_mid_v << " " << right_mid_v << "\n"; cerr << "left_cost = " << st_mid_cost << "\n"; cerr << "mid_cost = " << left_right_mid_cost << "\n"; cerr << "right_cost = " << mid_fn_cost << "\n"; best = max(best, cost); } } return best; } */ int main() { int queries_cnt; ios_base::sync_with_stdio(false); cin.tie(0); cin >> n >> m >> queries_cnt >> A >> B; //layer_size = max(100, (int)pow(n + m, 0.67)); // TODO: lepiej przemyslec //layer_size = 3; //cerr << "pamietaj o layer size\n"; //layers_cnt = (n + m + layer_size - 1) / layer_size; query.resize(queries_cnt); for (int i = 0; i < queries_cnt; i++) { int s1, f1, s2, f2; cin >> s1 >> f1 >> s2 >> f2; s1--; f1--; s2--; f2--; query[i] = Query(from_ord_pos(make_pair(s1, s2)), from_ord_pos(make_pair(f1, f2)), i); } for (int i = 0; i < queries_cnt; i++) query[i].answer = naive_dp(query[i].a, query[i].b); /* query_groups.resize(layers_cnt); for (const Query& q : query) { int qg = row_to_layer(q.b.first) - row_to_layer(q.a.first); query_groups[qg].push_back(q.idx); } for (int qid : query_groups[0]) { // queries inside layer query[qid].answer = naive_dp(query[qid].a, query[qid].b); } // jump between adjacent layers jump_next_layer.resize(layers_cnt); for (int lid = 0; lid < layers_cnt-1; lid++) { int row = layer_to_row(lid); int sz = row_size(row); jump_next_layer[lid].resize(sz); for (int which = 0; which < sz; which++) { jump_next_layer[lid][which] = rightdown_triangle_dp(make_pair(row, which), true); } } // initialize with jumps by 0 jump_few_layers.resize(layers_cnt); X_jump_few_layers.resize(layers_cnt); for (int lid = 0; lid < layers_cnt; lid++) { int row = layer_to_row(lid); int sz = row_size(row); jump_few_layers[lid].resize(sz); for (int which = 0; which < sz; which++) jump_few_layers[lid][which].push_back(make_pair(which, is_pos_good(lid, which))); } for (int ql = 1; ql < layers_cnt; ql++) { cerr << "ql = " << ql << "\n"; // solve queries jumping by ql layers for (int qid : query_groups[ql]) { vector<pair<int,short>> a_to_next_layer = rightdown_triangle_dp(query[qid].a); int mid_layer = row_to_layer(next_layer_splitter(query[qid].a.first)); vector<pair<int,short>> layer_to_prev_b = leftup_triangle_dp(query[qid].b); query[qid].answer = merge3( mid_layer, ql - 1, a_to_next_layer, jump_few_layers[mid_layer], layer_to_prev_b ); } // compute jumps to one layer further for (int lid = 0; lid < layers_cnt; lid++) { if (lid + ql - 1 >= layers_cnt) break; X_jump_few_layers[lid] = merge_jumps( lid, ql - 1, jump_few_layers[lid], jump_next_layer[lid + ql - 1]); } jump_few_layers = X_jump_few_layers; X_jump_few_layers.clear(); X_jump_few_layers.resize(layers_cnt); cerr << "\n\n\n\n\n\nnext level of jumps!\n"; for (int lid = 0; lid < layers_cnt; lid++) for (int which = 0; which < jump_few_layers[lid].size(); which++) for (const auto& pp : jump_few_layers[lid][which]) cerr << "Layer " << lid << ", node " << which << " can go to few next layers, node " << pp.first << " with LCS = " << pp.second << "\n"; } */ for (const Query& q : query) cout << q.answer << "\n"; return 0; }
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 | #include <bits/stdc++.h> using namespace std; typedef vector<vector<short>> Array; typedef vector<short> ArrayRow; typedef pair<int,int> Pos; typedef pair<int,int> OrdPos; /* typedef vector<vector<pair<int,short>>> LayerJumps; */ //int layer_size, layers_cnt; struct Query { Pos a, b; int idx; int answer; Query(): answer(-1) {}; Query(Pos _a, Pos _b, int _idx): a(_a), b(_b), idx(_idx), answer(-1) {}; }; string A, B; int n, m; bool inside(const OrdPos& p) { return (p.first >= 0) && (p.second >= 0) && (p.first < n) && (p.second < m); } inline Pos from_ord_pos(const OrdPos& p) { int row = p.first + p.second; int which = (row < m) ? (p.first) : (p.first - row + (m-1)); return make_pair(row, which); } inline OrdPos to_ord_pos(const Pos& p) { int y = (p.first < m) ? (p.second) : (p.first + p.second - (m-1)); int x = p.first - y; return make_pair(y, x); } /* inline int row_size(int r) { return min(min(n, m), min(r, n + m - r)) + 1; } inline int row_to_layer(int r) { return r / layer_size; } inline int layer_to_row(int l) { return l * layer_size; } inline int next_layer_splitter(int r) { return layer_to_row(row_to_layer(r + layer_size - 1)); } inline int prev_layer_splitter(int r) { return layer_to_row(row_to_layer(r)); } inline void initialize(vector<vector<int>>& v, int sz) { v.resize(sz, vector<int>()); for (int i = 0; i < sz; i++) v[i].resize(sz - i); } */ inline short safe_get(const Array& dp, int i, int j) { if ((i < 0) || (j < 0)) return 0; return dp[i][j]; } inline short smax(short a, short b) { return (a > b) ? a : b; } inline short smax(short a, short b, short c) { return smax(smax(a, b), c); } inline char get_char(const string& s, int p, char fail_char) { if ((p >= 0) && (p < s.length())) return s[p]; return fail_char; } /* inline int is_pos_good(const Pos& p) { OrdPos q = to_ord_pos(p); return get_char(A, q.first, '$') == get_char(B, q.second, '#'); } inline int is_pos_good(int layer, int which) { return is_pos_good(make_pair(layer_to_row(layer), which)); } */ int naive_dp(const Pos& a, const Pos& b) { OrdPos ap = to_ord_pos(a); OrdPos bp = to_ord_pos(b); int height = bp.first - ap.first + 1; int width = bp.second - ap.second + 1; Array dp(height, ArrayRow(width, 0)); for (int i = 0; i < height; i++) for (int j = 0; j < width; j++) { if (get_char(A, ap.first + i, '$') == get_char(B, ap.second + j, '#')) dp[i][j] = smax(dp[i][j], safe_get(dp, i-1, j-1) + 1); else dp[i][j] = smax(dp[i][j], safe_get(dp, i-1, j), safe_get(dp, i, j-1)); } return dp[height-1][width-1]; } vector<Query> query; /* vector<vector<int>> query_groups; vector<pair<int,short>> rightdown_triangle_dp(const Pos& x, bool go_next = false) { OrdPos p = to_ord_pos(x); int sz = next_layer_splitter(x.first + (int)go_next) - x.first + 1; Array dp(sz, ArrayRow(sz, -1)); for (int i = 0; i < sz; i++) for (int j = 0; i+j < sz; j++) { if (get_char(A, p.first + i, '$') == get_char(B, p.second + j, '#')) dp[i][j] = smax(dp[i][j], safe_get(dp, i-1, j-1) + 1); else dp[i][j] = smax(dp[i][j], safe_get(dp, i-1, j), safe_get(dp, i, j-1)); } vector<pair<int,short>> results; for (int i = 0; i < sz; i++) { OrdPos q = make_pair(p.first + i, p.second + (sz - 1 - i)); if (!inside(q)) continue; Pos rq = from_ord_pos(q); results.push_back(make_pair(rq.second, dp[i][sz-1-i])); } return results; } vector<pair<int,short>> leftup_triangle_dp(const Pos& x) { OrdPos p = to_ord_pos(x); int sz = x.first - prev_layer_splitter(x.first) + 1; Array dp(sz, ArrayRow(sz, -1)); for (int i = 0; i < sz; i++) for (int j = 0; i+j < sz; j++) { if (get_char(A, p.first - i, '$') == get_char(B, p.second - j, '#')) dp[i][j] = smax(dp[i][j], safe_get(dp, i-1, j-1) + 1); else dp[i][j] = smax(dp[i][j], safe_get(dp, i-1, j), safe_get(dp, i, j-1)); } vector<pair<int,short>> results; for (int i = 0; i < sz; i++) { OrdPos q = make_pair(p.first - i, p.second - (sz - 1 - i)); if (!inside(q)) continue; Pos rq = from_ord_pos(q); results.push_back(make_pair(rq.second, dp[i][sz-1-i])); } return results; } vector<LayerJumps> jump_next_layer; vector<LayerJumps> jump_few_layers; vector<LayerJumps> X_jump_few_layers; LayerJumps merge_jumps(int lid, int ldiff, const LayerJumps& jumps1, const LayerJumps& jumps2) { int mid_v, cost_st_mid, fn_v, cost_mid_fn; LayerJumps result(jumps1.size()); for (int st_v = 0; st_v < jumps1.size(); st_v++) { unordered_map<int,short> st_result; for (const auto& mid_jump : jumps1[st_v]) { mid_v = mid_jump.first; if (jumps2.empty()) break; if (mid_v >= jumps2.size()) continue; cost_st_mid = mid_jump.second - is_pos_good(lid + ldiff, mid_v); for (const auto& fn_jump : jumps2[mid_v]) { fn_v = fn_jump.first; cost_mid_fn = fn_jump.second; cerr << "jump from " << lid << " " << st_v << " through " << lid + ldiff << " " << mid_v << " to end in " << lid + ldiff + 1 << " " << fn_v << " for costs " << cost_st_mid + is_pos_good(lid + ldiff, mid_v) << " and " << cost_mid_fn << " (" << is_pos_good(lid + ldiff, mid_v) << ") = " << cost_st_mid + cost_mid_fn << "\n"; if ((st_result.count(fn_v) == 0) || (st_result[fn_v] < cost_st_mid + cost_mid_fn)) { st_result[fn_v] = cost_st_mid + cost_mid_fn; } } } result[st_v] = vector<pair<int,short>>(st_result.begin(), st_result.end()); } return result; } int merge3(int lid, int ldiff, const vector<pair<int,short>>& st_jumps, const LayerJumps& mid_jumps, const vector<pair<int,short>>& jumps_fn) { unordered_map<int,short> st_jumps_lookup(st_jumps.begin(), st_jumps.end()); unordered_map<int,short> jumps_fn_lookup(jumps_fn.begin(), jumps_fn.end()); int best = 0; int right_mid_v, left_right_mid_cost, st_mid_cost, mid_fn_cost, cost; for (int left_mid_v = 0; left_mid_v < mid_jumps.size(); left_mid_v++) { if (st_jumps_lookup.count(left_mid_v) == 0) continue; st_mid_cost = st_jumps_lookup.at(left_mid_v) - is_pos_good(lid, left_mid_v); if ((mid_jumps.empty()) || (left_mid_v >= mid_jumps.size())) continue; for (const auto& right_mid_jump : mid_jumps[left_mid_v]) { if (jumps_fn_lookup.count(right_mid_v) == 0) continue; right_mid_v = right_mid_jump.first; left_right_mid_cost = right_mid_jump.second - is_pos_good(lid + ldiff, right_mid_v); mid_fn_cost = jumps_fn_lookup.at(right_mid_v); cost = st_mid_cost + left_right_mid_cost + mid_fn_cost; cerr << "go through big jump " << left_mid_v << " " << right_mid_v << "\n"; cerr << "left_cost = " << st_mid_cost << "\n"; cerr << "mid_cost = " << left_right_mid_cost << "\n"; cerr << "right_cost = " << mid_fn_cost << "\n"; best = max(best, cost); } } return best; } */ int main() { int queries_cnt; ios_base::sync_with_stdio(false); cin.tie(0); cin >> n >> m >> queries_cnt >> A >> B; //layer_size = max(100, (int)pow(n + m, 0.67)); // TODO: lepiej przemyslec //layer_size = 3; //cerr << "pamietaj o layer size\n"; //layers_cnt = (n + m + layer_size - 1) / layer_size; query.resize(queries_cnt); for (int i = 0; i < queries_cnt; i++) { int s1, f1, s2, f2; cin >> s1 >> f1 >> s2 >> f2; s1--; f1--; s2--; f2--; query[i] = Query(from_ord_pos(make_pair(s1, s2)), from_ord_pos(make_pair(f1, f2)), i); } for (int i = 0; i < queries_cnt; i++) query[i].answer = naive_dp(query[i].a, query[i].b); /* query_groups.resize(layers_cnt); for (const Query& q : query) { int qg = row_to_layer(q.b.first) - row_to_layer(q.a.first); query_groups[qg].push_back(q.idx); } for (int qid : query_groups[0]) { // queries inside layer query[qid].answer = naive_dp(query[qid].a, query[qid].b); } // jump between adjacent layers jump_next_layer.resize(layers_cnt); for (int lid = 0; lid < layers_cnt-1; lid++) { int row = layer_to_row(lid); int sz = row_size(row); jump_next_layer[lid].resize(sz); for (int which = 0; which < sz; which++) { jump_next_layer[lid][which] = rightdown_triangle_dp(make_pair(row, which), true); } } // initialize with jumps by 0 jump_few_layers.resize(layers_cnt); X_jump_few_layers.resize(layers_cnt); for (int lid = 0; lid < layers_cnt; lid++) { int row = layer_to_row(lid); int sz = row_size(row); jump_few_layers[lid].resize(sz); for (int which = 0; which < sz; which++) jump_few_layers[lid][which].push_back(make_pair(which, is_pos_good(lid, which))); } for (int ql = 1; ql < layers_cnt; ql++) { cerr << "ql = " << ql << "\n"; // solve queries jumping by ql layers for (int qid : query_groups[ql]) { vector<pair<int,short>> a_to_next_layer = rightdown_triangle_dp(query[qid].a); int mid_layer = row_to_layer(next_layer_splitter(query[qid].a.first)); vector<pair<int,short>> layer_to_prev_b = leftup_triangle_dp(query[qid].b); query[qid].answer = merge3( mid_layer, ql - 1, a_to_next_layer, jump_few_layers[mid_layer], layer_to_prev_b ); } // compute jumps to one layer further for (int lid = 0; lid < layers_cnt; lid++) { if (lid + ql - 1 >= layers_cnt) break; X_jump_few_layers[lid] = merge_jumps( lid, ql - 1, jump_few_layers[lid], jump_next_layer[lid + ql - 1]); } jump_few_layers = X_jump_few_layers; X_jump_few_layers.clear(); X_jump_few_layers.resize(layers_cnt); cerr << "\n\n\n\n\n\nnext level of jumps!\n"; for (int lid = 0; lid < layers_cnt; lid++) for (int which = 0; which < jump_few_layers[lid].size(); which++) for (const auto& pp : jump_few_layers[lid][which]) cerr << "Layer " << lid << ", node " << which << " can go to few next layers, node " << pp.first << " with LCS = " << pp.second << "\n"; } */ for (const Query& q : query) cout << q.answer << "\n"; return 0; } |