/usr/include/sdsl/k2_treap.hpp is in libsdsl-dev 2.0.3-4.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 | /* sdsl - succinct data structures library
Copyright (C) 2014 Simon Gog
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see http://www.gnu.org/licenses/ .
*/
/*! \file k2_treap.hpp
\brief k2_treap.hpp contains a compact k^2-treap.
\author Simon Gog
*/
#ifndef INCLUDED_SDSL_K2_TREAP
#define INCLUDED_SDSL_K2_TREAP
#include "sdsl/vectors.hpp"
#include "sdsl/bits.hpp"
#include "sdsl/k2_treap_helper.hpp"
#include "sdsl/k2_treap_algorithm.hpp"
#include <tuple>
#include <algorithm>
#include <climits>
#include <vector>
//! Namespace for the succinct data structure library.
namespace sdsl
{
//! A k^2-treap.
/*! A k^2-treap is an indexing structure for a set of weighted points. The set
* consists of triples (x,y,w), where the first two components x and y are
* the coordinates of the point and w is the point's weight.
*
* The k^2 treap supports 4-sided range count queries and 4-sided prioritized
* range queries in 2d. Using the latter functionality it is also possible to
* support 6-sided range queries in 3d. An example can be found in
* examples/k2_treap_in_mem.cpp .
*
* The k^2-treap constructed in-place. The construct method expects either
* a vector of std::array<X,3> elements (each array represent a tuple x,y,w)
* or a file prefix FILE. In the latter case three serialized int_vector<>
* have to be present at FILE.x, FILE.y, and FILE.w. One int_vector<> per
* component.
*
* \par References
* [1] N. Brisaboa, G. de Bernardo, R. Konow, and G. Navarro:
* ,,$K^2$-Treaps: Range Top-$k$ Queries in Compact Space,
* Proceedings of SPIRE 2014.
*/
template<uint8_t t_k,
typename t_bv=bit_vector,
typename t_rank=typename t_bv::rank_1_type,
typename t_max_vec=dac_vector<>>
class k2_treap
{
static_assert(t_k>1, "t_k has to be larger than 1.");
static_assert(t_k<=16, "t_k has to be smaller than 17.");
public:
typedef int_vector<>::size_type size_type;
using node_type = k2_treap_ns::node_type;
using point_type = k2_treap_ns::point_type;
using t_p = k2_treap_ns::t_p;
enum { k = t_k };
private:
uint8_t m_t = 0;
t_bv m_bp;
t_rank m_bp_rank;
t_max_vec m_maxval;
std::vector<int_vector<>> m_coord;
int_vector<64> m_level_idx;
template<typename t_tv>
uint8_t get_t(const t_tv& v)
{
using namespace k2_treap_ns;
if (v.size() == 0) {
return 0;
}
using t_e = typename t_tv::value_type;
auto tupmax = [](t_e a) {
return std::max(std::get<0>(a),std::get<1>(a));
};
auto max_it = std::max_element(std::begin(v), std::end(v), [&](t_e a, t_e b) {
return tupmax(a) < tupmax(b);
});
uint64_t x = tupmax(*max_it);
uint8_t res = 0;
while (precomp<t_k>::exp(res) <= x) { ++res; }
return res;
}
public:
uint8_t& t = m_t;
k2_treap() = default;
k2_treap(const k2_treap& tr)
{
*this = tr;
}
k2_treap(k2_treap&& tr)
{
*this = std::move(tr);
}
//! Move assignment operator
k2_treap& operator=(k2_treap&& tr)
{
if (this != &tr) {
m_t = tr.m_t;
m_bp = std::move(tr.m_bp);
m_bp_rank = std::move(tr.m_bp_rank);
m_bp_rank.set_vector(&m_bp);
m_maxval = std::move(tr.m_maxval);
m_coord = std::move(tr.m_coord);
m_level_idx = std::move(tr.m_level_idx);
}
return *this;
}
//! Assignment operator
k2_treap& operator=(k2_treap& tr)
{
if (this != &tr) {
m_t = tr.m_t;
m_bp = tr.m_bp;
m_bp_rank = tr.m_bp_rank;
m_bp_rank.set_vector(&m_bp);
m_maxval = tr.m_maxval;
m_coord = tr.m_coord;
m_level_idx = tr.m_level_idx;
}
return *this;
}
//! Number of points in the 2^k treap
size_type
size() const
{
return m_maxval.size();
}
//! Swap operator
void swap(k2_treap& tr)
{
if (this != &tr) {
std::swap(m_t, tr.m_t);
m_bp.swap(tr.m_bp);
util::swap_support(m_bp_rank, tr.m_bp_rank, &m_bp, &(tr.m_bp));
m_maxval.swap(tr.m_maxval);
m_coord.swap(tr.m_coord);
m_level_idx.swap(tr.m_level_idx);
}
}
k2_treap(int_vector_buffer<>& buf_x,
int_vector_buffer<>& buf_y,
int_vector_buffer<>& buf_w)
{
using namespace k2_treap_ns;
typedef int_vector_buffer<>* t_buf_p;
std::vector<t_buf_p> bufs = {&buf_x, &buf_y, &buf_w};
auto max_element = [](int_vector_buffer<>& buf) {
uint64_t max_val = 0;
for (auto val : buf) {
max_val = std::max((uint64_t)val, max_val);
}
return max_val;
};
auto max_buf_element = [&]() {
uint64_t max_v = 0;
for (auto buf : bufs) {
uint64_t _max_v = max_element(*buf);
max_v = std::max(max_v, _max_v);
}
return max_v;
};
uint64_t x = max_buf_element();
uint8_t res = 0;
while (res <= 64 and precomp<t_k>::exp(res) <= x) { ++res; }
if (res == 65) {
throw std::logic_error("Maximal element of input is too big.");
}
if (precomp<t_k>::exp(res) <= std::numeric_limits<uint32_t>::max()) {
auto v = read<uint32_t,uint32_t,uint32_t>(bufs);
construct(v, buf_x.filename());
} else {
auto v = read<uint64_t,uint64_t,uint64_t>(bufs);
construct(v, buf_x.filename());
}
}
template<typename t_x=uint64_t, typename t_y=uint64_t, typename t_w=uint64_t>
std::vector<std::tuple<t_x, t_y, t_w>>
read(std::vector<int_vector_buffer<>*>& bufs)
{
typedef std::vector<std::tuple<t_x, t_y, t_w>> t_tuple_vec;
t_tuple_vec v = t_tuple_vec(bufs[0]->size());
for (uint64_t j=0; j<v.size(); ++j) {
std::get<0>(v[j]) = (*(bufs[0]))[j];
}
for (uint64_t j=0; j<v.size(); ++j) {
std::get<1>(v[j]) = (*(bufs[1]))[j];
}
for (uint64_t j=0; j<v.size(); ++j) {
std::get<2>(v[j]) = (*(bufs[2]))[j];
}
return v;
}
template<typename t_x, typename t_y, typename t_w>
k2_treap(std::vector<std::tuple<t_x, t_y, t_w>>& v, std::string temp_file_prefix="")
{
if (v.size() > 0) {
construct(v, temp_file_prefix);
}
}
template<typename t_x, typename t_y, typename t_w>
void construct(std::vector<std::tuple<t_x, t_y, t_w>>& v, std::string temp_file_prefix="")
{
using namespace k2_treap_ns;
using t_e = std::tuple<t_x, t_y, t_w>;
m_t = get_t(v);
uint64_t M = precomp<t_k>::exp(t);
t_e MM = t_e(M,M,M);
std::string id_part = util::to_string(util::pid())
+ "_" + util::to_string(util::id());
m_coord.resize(t);
m_level_idx = int_vector<64>(1+t, 0);
std::string val_file = temp_file_prefix + "_k2_treap_"
+ id_part + ".sdsl";
std::string bp_file = temp_file_prefix + "_bp_" + id_part
+ ".sdsl";
{
int_vector_buffer<> val_buf(val_file, std::ios::out);
int_vector_buffer<1> bp_buf(bp_file, std::ios::out);
auto end = std::end(v);
uint64_t last_level_nodes = 1;
uint64_t level_nodes;
for (uint64_t l=t, cc=0; l+1 > 0; --l) {
if (l > 0) {
m_level_idx[l-1] = m_level_idx[l] + last_level_nodes;
m_coord[l-1] = int_vector<>(2*last_level_nodes,0, bits::hi(precomp<t_k>::exp(l))+1);
}
level_nodes = 0;
cc = 0;
auto sp = std::begin(v);
for (auto ep = sp; ep != end;) {
ep = std::find_if(sp, end, [&sp,&l](const t_e& e) {
auto x1 = std::get<0>(*sp);
auto y1 = std::get<1>(*sp);
auto x2 = std::get<0>(e);
auto y2 = std::get<1>(e);
return precomp<t_k>::divexp(x1,l) != precomp<t_k>::divexp(x2,l)
or precomp<t_k>::divexp(y1,l) != precomp<t_k>::divexp(y2,l);
});
auto max_it = std::max_element(sp, ep, [](t_e a, t_e b) {
if (std::get<2>(a) != std::get<2>(b))
return std::get<2>(a) < std::get<2>(b);
else if (std::get<0>(a) != std::get<0>(b))
return std::get<0>(a) > std::get<0>(b);
return std::get<1>(a) > std::get<1>(b);
});
if (l > 0) {
m_coord[l-1][2*cc] = precomp<t_k>::modexp(std::get<0>(*max_it), l);
m_coord[l-1][2*cc+1] = precomp<t_k>::modexp(std::get<1>(*max_it), l);
++cc;
}
val_buf.push_back(std::get<2>(*max_it));
*max_it = MM;
--ep;
std::swap(*max_it, *ep);
if (l > 0) {
auto _sp = sp;
for (uint8_t i=0; i < t_k; ++i) {
auto _ep = ep;
if (i+1 < t_k) {
_ep = std::partition(_sp, ep, [&i,&l](const t_e& e) {
return precomp<t_k>::divexp(std::get<0>(e),l-1)%t_k <= i;
});
}
auto __sp = _sp;
for (uint8_t j=0; j < t_k; ++j) {
auto __ep = _ep;
if (j+1 < t_k) {
__ep = std::partition(__sp, _ep, [&j,&l](const t_e& e) {
return precomp<t_k>::divexp(std::get<1>(e),l-1)%t_k <= j;
});
}
bool not_empty = __ep > __sp;
bp_buf.push_back(not_empty);
level_nodes += not_empty;
__sp = __ep;
}
_sp = _ep;
}
}
++ep;
sp = ep;
}
end = std::remove_if(begin(v), end, [&](t_e e) {
return e == MM;
});
last_level_nodes = level_nodes;
}
}
bit_vector bp;
load_from_file(bp, bp_file);
{
int_vector_buffer<> val_rw(val_file, std::ios::in | std::ios::out);
int_vector_buffer<> val_r(val_file, std::ios::in);
uint64_t bp_idx = bp.size();
uint64_t r_idx = m_level_idx[0];
uint64_t rw_idx = val_rw.size();
while (bp_idx > 0) {
--r_idx;
for (size_t i=0; i < t_k*t_k; ++i) {
if (bp[--bp_idx]) {
--rw_idx;
val_rw[rw_idx] = val_r[r_idx] - val_rw[rw_idx];
}
}
}
}
{
int_vector_buffer<> val_r(val_file);
m_maxval = t_max_vec(val_r);
}
{
bit_vector _bp;
_bp.swap(bp);
m_bp = t_bv(_bp);
}
util::init_support(m_bp_rank, &m_bp);
sdsl::remove(bp_file);
sdsl::remove(val_file);
}
//! Serializes the data structure into the given ostream
size_type serialize(std::ostream& out, structure_tree_node* v=nullptr,
std::string name="")const
{
structure_tree_node* child = structure_tree::add_child(
v, name, util::class_name(*this));
size_type written_bytes = 0;
written_bytes += write_member(m_t, out, child, "t");
written_bytes += m_bp.serialize(out, child, "bp");
written_bytes += m_bp_rank.serialize(out, child, "bp_rank");
written_bytes += serialize_vector(m_coord, out, child, "coord");
written_bytes += m_maxval.serialize(out, child, "maxval");
written_bytes += m_level_idx.serialize(out, child, "level_idx");
structure_tree::add_size(child, written_bytes);
return written_bytes;
}
//! Loads the data structure from the given istream.
void load(std::istream& in)
{
read_member(m_t, in);
m_bp.load(in);
m_bp_rank.load(in);
m_bp_rank.set_vector(&m_bp);
m_coord.resize(t);
load_vector(m_coord, in);
m_maxval.load(in);
m_level_idx.load(in);
}
node_type
root() const
{
return node_type(t, t_p(0,0), 0, m_maxval[0],
t_p(m_coord[t-1][0], m_coord[t-1][1]));
}
bool
is_leaf(const node_type& v) const
{
return v.idx >= m_bp.size();
}
std::vector<node_type>
children(const node_type& v) const
{
using namespace k2_treap_ns;
std::vector<node_type> res;
if (!is_leaf(v)) {
uint64_t rank = m_bp_rank(v.idx);
auto x = std::real(v.p);
auto y = std::imag(v.p);
for (size_t i=0; i<t_k; ++i) {
for (size_t j=0; j<t_k; ++j) {
// get_int better for compressed bitvectors
// or introduce cache for bitvectors
if (m_bp[v.idx+t_k*i+j]) {
++rank;
auto _x = x + i*precomp<t_k>::exp(v.t-1);
auto _y = y + j*precomp<t_k>::exp(v.t-1);
auto _max_v = v.max_v - m_maxval[rank];
auto _max_p = t_p(_x, _y);
if (v.t > 1) {
auto y = rank-m_level_idx[v.t-1];
_max_p = t_p(_x+m_coord[v.t-2][2*y],
_y+m_coord[v.t-2][2*y+1]);
}
res.emplace_back(v.t-1, t_p(_x,_y), rank*t_k*t_k,
_max_v, _max_p);
}
}
}
}
return res;
}
};
}
#endif
|