cplib-cpp
This documentation is automatically generated by online-judge-tools/verification-helper
Lazy Segtree (based on atcoder::lazy_segtree)
(segmenttree/acl_lazysegtree.hpp)
- View this file on GitHub
- Last update: 2025-08-24 23:32:38+09:00
- Include:
#include "segmenttree/acl_lazysegtree.hpp" - Link: https://atcoder.github.io/ac-library/production/document_ja/lazysegtree.html
- Link: https://betrue12.hateblo.jp/entry/2020/09/22/194541
- Link: https://betrue12.hateblo.jp/entry/2020/09/23/005940
ACL-based lazy segtree
Example
struct S {};
S op(S l, S r) {
return {};
}
S e() { return {}; };
using F = bool;
S mp(F f, S x) {
return x;
}
F composition(F fnew, F gold) { return fnew ^ gold; }
F id() { return false; }
vector<S> A;
atcoder::lazy_segtree<S, op, e, F, mp, composition, id> seg(A);
Link
Required by
- Segment Tree Beats (based on atcoder::lazy_segtree)
(segmenttree/acl_beats.hpp)
segmenttree/trees/acl_range-add-chmax-range-min.hpp
- segmenttree/trees/acl_range-add-chmax-range-sum.hpp
- segmenttree/trees/acl_range-affine-range-sum.hpp
- segmenttree/trees/acl_range-bitwiseandor-range-max.hpp
- segmenttree/trees/acl_range-update-gcd-range-max-sum.hpp
- segmenttree/trees/acl_range-update-range-sum-min.hpp
Verified with
- segmenttree/test/acl_range-affine-range-sum.test.cpp
- segmenttree/test/beats.test.cpp
- segmenttree/test/beats_gcd.test.cpp
- segmenttree/test/beats_random_test.test.cpp
- segmenttree/test/beats_range-add-chmax-range-sum.test.cpp
Code
#ifndef ATCODER_INTERNAL_BITOP_HPP
#define ATCODER_INTERNAL_BITOP_HPP 1
#ifdef _MSC_VER
#include <intrin.h>
#endif
#if __cplusplus >= 202002L
#include <bit>
#endif
namespace atcoder {
namespace internal {
#if __cplusplus >= 202002L
using std::bit_ceil;
#else
// @return same with std::bit::bit_ceil
unsigned int bit_ceil(unsigned int n) {
unsigned int x = 1;
while (x < (unsigned int)(n)) x *= 2;
return x;
}
#endif
// @param n `1 <= n`
// @return same with std::bit::countr_zero
int countr_zero(unsigned int n) {
#ifdef _MSC_VER
unsigned long index;
_BitScanForward(&index, n);
return index;
#else
return __builtin_ctz(n);
#endif
}
// @param n `1 <= n`
// @return same with std::bit::countr_zero
constexpr int countr_zero_constexpr(unsigned int n) {
int x = 0;
while (!(n & (1 << x))) x++;
return x;
}
} // namespace internal
} // namespace atcoder
#endif // ATCODER_INTERNAL_BITOP_HPP
#ifndef ATCODER_LAZYSEGTREE_HPP
#define ATCODER_LAZYSEGTREE_HPP 1
#include <cassert>
#include <functional>
#include <vector>
#include "atcoder/internal_bit"
namespace atcoder {
template <class S, auto op, auto e, class F, auto mapping, auto composition, auto id>
struct lazy_segtree {
static_assert(std::is_convertible_v<decltype(op), std::function<S(S, S)>>,
"op must work as S(S, S)");
static_assert(std::is_convertible_v<decltype(e), std::function<S()>>, "e must work as S()");
static_assert(std::is_convertible_v<decltype(mapping), std::function<S(F, S)>>,
"mapping must work as S(F, S)");
static_assert(std::is_convertible_v<decltype(composition), std::function<F(F, F)>>,
"composition must work as F(F, F)");
static_assert(std::is_convertible_v<decltype(id), std::function<F()>>, "id must work as F()");
public:
lazy_segtree() : lazy_segtree(0) {}
explicit lazy_segtree(int n) : lazy_segtree(std::vector<S>(n, e())) {}
explicit lazy_segtree(const std::vector<S> &v) : _n(int(v.size())) {
size = (int)internal::bit_ceil((unsigned int)(_n));
log = internal::countr_zero((unsigned int)size);
d = std::vector<S>(2 * size, e());
lz = std::vector<F>(size, id());
for (int i = 0; i < _n; i++) d[size + i] = v[i];
for (int i = size - 1; i >= 1; i--) { update(i); }
}
void set(int p, S x) {
assert(0 <= p && p < _n);
p += size;
for (int i = log; i >= 1; i--) push(p >> i);
d[p] = x;
for (int i = 1; i <= log; i++) update(p >> i);
}
S get(int p) {
assert(0 <= p && p < _n);
p += size;
for (int i = log; i >= 1; i--) push(p >> i);
return d[p];
}
S prod(int l, int r) {
assert(0 <= l && l <= r && r <= _n);
if (l == r) return e();
l += size;
r += size;
for (int i = log; i >= 1; i--) {
if (((l >> i) << i) != l) push(l >> i);
if (((r >> i) << i) != r) push((r - 1) >> i);
}
S sml = e(), smr = e();
while (l < r) {
if (l & 1) sml = op(sml, d[l++]);
if (r & 1) smr = op(d[--r], smr);
l >>= 1;
r >>= 1;
}
return op(sml, smr);
}
S all_prod() { return d[1]; }
void apply(int p, F f) {
assert(0 <= p && p < _n);
p += size;
for (int i = log; i >= 1; i--) push(p >> i);
d[p] = mapping(f, d[p]);
for (int i = 1; i <= log; i++) update(p >> i);
}
void apply(int l, int r, F f) {
assert(0 <= l && l <= r && r <= _n);
if (l == r) return;
l += size;
r += size;
for (int i = log; i >= 1; i--) {
if (((l >> i) << i) != l) push(l >> i);
if (((r >> i) << i) != r) push((r - 1) >> i);
}
{
int l2 = l, r2 = r;
while (l < r) {
if (l & 1) all_apply(l++, f);
if (r & 1) all_apply(--r, f);
l >>= 1;
r >>= 1;
}
l = l2;
r = r2;
}
for (int i = 1; i <= log; i++) {
if (((l >> i) << i) != l) update(l >> i);
if (((r >> i) << i) != r) update((r - 1) >> i);
}
}
template <bool (*g)(S)> int max_right(int l) {
return max_right(l, [](S x) { return g(x); });
}
template <class G> int max_right(int l, G g) {
assert(0 <= l && l <= _n);
assert(g(e()));
if (l == _n) return _n;
l += size;
for (int i = log; i >= 1; i--) push(l >> i);
S sm = e();
do {
while (l % 2 == 0) l >>= 1;
if (!g(op(sm, d[l]))) {
while (l < size) {
push(l);
l = (2 * l);
if (g(op(sm, d[l]))) {
sm = op(sm, d[l]);
l++;
}
}
return l - size;
}
sm = op(sm, d[l]);
l++;
} while ((l & -l) != l);
return _n;
}
template <bool (*g)(S)> int min_left(int r) {
return min_left(r, [](S x) { return g(x); });
}
template <class G> int min_left(int r, G g) {
assert(0 <= r && r <= _n);
assert(g(e()));
if (r == 0) return 0;
r += size;
for (int i = log; i >= 1; i--) push((r - 1) >> i);
S sm = e();
do {
r--;
while (r > 1 && (r % 2)) r >>= 1;
if (!g(op(d[r], sm))) {
while (r < size) {
push(r);
r = (2 * r + 1);
if (g(op(d[r], sm))) {
sm = op(d[r], sm);
r--;
}
}
return r + 1 - size;
}
sm = op(d[r], sm);
} while ((r & -r) != r);
return 0;
}
protected:
int _n, size, log;
std::vector<S> d;
std::vector<F> lz;
void update(int k) { d[k] = op(d[2 * k], d[2 * k + 1]); }
virtual void all_apply(int k, F f) {
d[k] = mapping(f, d[k]);
if (k < size) lz[k] = composition(f, lz[k]);
}
void push(int k) {
all_apply(2 * k, lz[k]);
all_apply(2 * k + 1, lz[k]);
lz[k] = id();
}
};
} // namespace atcoder
#endif // ATCODER_LAZYSEGTREE_HPP
// Reference: https://atcoder.github.io/ac-library/production/document_ja/lazysegtree.html
// https://betrue12.hateblo.jp/entry/2020/09/22/194541
// https://betrue12.hateblo.jp/entry/2020/09/23/005940
/*
struct S {};
S op(S l, S r) {
return {};
}
S e() { return {}; };
using F = bool;
S mp(F f, S x) {
return x;
}
F composition(F fnew, F gold) { return fnew ^ gold; }
F id() { return false; }
vector<S> A;
atcoder::lazy_segtree<S, op, e, F, mp, composition, id> seg(A);
*/Traceback (most recent call last):
File "/opt/hostedtoolcache/Python/3.13.7/x64/lib/python3.13/site-packages/onlinejudge_verify/documentation/build.py", line 71, in _render_source_code_stat
bundled_code = language.bundle(stat.path, basedir=basedir, options={'include_paths': [basedir]}).decode()
~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/opt/hostedtoolcache/Python/3.13.7/x64/lib/python3.13/site-packages/onlinejudge_verify/languages/cplusplus.py", line 187, in bundle
bundler.update(path)
~~~~~~~~~~~~~~^^^^^^
File "/opt/hostedtoolcache/Python/3.13.7/x64/lib/python3.13/site-packages/onlinejudge_verify/languages/cplusplus_bundle.py", line 355, in update
raise BundleErrorAt(path, i + 1, "found codes out of include guard")
onlinejudge_verify.languages.cplusplus_bundle.BundleErrorAt: segmenttree/acl_lazysegtree.hpp: line 56: found codes out of include guard