870 lines
23 KiB
C++
870 lines
23 KiB
C++
/* Algorithms for libostd.
|
|
*
|
|
* This file is part of libostd. See COPYING.md for futher information.
|
|
*/
|
|
|
|
#ifndef OSTD_ALGORITHM_HH
|
|
#define OSTD_ALGORITHM_HH
|
|
|
|
#include <math.h>
|
|
|
|
#include <utility>
|
|
#include <functional>
|
|
#include <type_traits>
|
|
#include <algorithm>
|
|
|
|
#include "ostd/range.hh"
|
|
|
|
namespace ostd {
|
|
|
|
/* partitioning */
|
|
|
|
template<typename R, typename U>
|
|
inline R partition(R range, U pred) {
|
|
R ret = range;
|
|
for (; !range.empty(); range.pop_front()) {
|
|
if (pred(range.front())) {
|
|
using std::swap;
|
|
swap(range.front(), ret.front());
|
|
ret.pop_front();
|
|
}
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
template<typename F>
|
|
inline auto partition(F &&func) {
|
|
return [func = std::forward<F>(func)](auto &&obj) mutable {
|
|
return partition(
|
|
std::forward<decltype(obj)>(obj), std::forward<F>(func)
|
|
);
|
|
};
|
|
}
|
|
|
|
template<typename R, typename P>
|
|
inline bool is_partitioned(R range, P pred) {
|
|
for (; !range.empty() && pred(range.front()); range.pop_front());
|
|
for (; !range.empty(); range.pop_front()) {
|
|
if (pred(range.front())) {
|
|
return false;
|
|
}
|
|
}
|
|
return true;
|
|
}
|
|
|
|
template<typename F>
|
|
inline auto is_partitioned(F &&func) {
|
|
return [func = std::forward<F>(func)](auto &&obj) mutable {
|
|
return is_partitioned(
|
|
std::forward<decltype(obj)>(obj), std::forward<F>(func)
|
|
);
|
|
};
|
|
}
|
|
|
|
/* sorting */
|
|
|
|
namespace detail {
|
|
template<typename R, typename C>
|
|
static void insort(R range, C &compare) {
|
|
range_size_t<R> rlen = range.size();
|
|
for (range_size_t<R> i = 1; i < rlen; ++i) {
|
|
range_size_t<R> j = i;
|
|
range_value_t<R> v{std::move(range[i])};
|
|
while (j > 0 && !compare(range[j - 1], v)) {
|
|
range[j] = std::move(range[j - 1]);
|
|
--j;
|
|
}
|
|
range[j] = std::move(v);
|
|
}
|
|
}
|
|
|
|
template<typename R, typename C>
|
|
static void hs_sift_down(
|
|
R range, range_size_t<R> s, range_size_t<R> e, C &compare
|
|
) {
|
|
range_size_t<R> r = s;
|
|
while ((r * 2 + 1) <= e) {
|
|
range_size_t<R> ch = r * 2 + 1;
|
|
range_size_t<R> sw = r;
|
|
if (compare(range[sw], range[ch])) {
|
|
sw = ch;
|
|
}
|
|
if (((ch + 1) <= e) && compare(range[sw], range[ch + 1])) {
|
|
sw = ch + 1;
|
|
}
|
|
if (sw != r) {
|
|
using std::swap;
|
|
swap(range[r], range[sw]);
|
|
r = sw;
|
|
} else {
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
|
|
template<typename R, typename C>
|
|
static void heapsort(R range, C &compare) {
|
|
range_size_t<R> len = range.size();
|
|
range_size_t<R> st = (len - 2) / 2;
|
|
for (;;) {
|
|
detail::hs_sift_down(range, st, len - 1, compare);
|
|
if (st-- == 0) {
|
|
break;
|
|
}
|
|
}
|
|
range_size_t<R> e = len - 1;
|
|
while (e > 0) {
|
|
using std::swap;
|
|
swap(range[e], range[0]);
|
|
--e;
|
|
detail::hs_sift_down(range, 0, e, compare);
|
|
}
|
|
}
|
|
|
|
template<typename R, typename C>
|
|
static void introloop(R range, C &compare, range_size_t<R> depth) {
|
|
using std::swap;
|
|
if (range.size() <= 10) {
|
|
detail::insort(range, compare);
|
|
return;
|
|
}
|
|
if (depth == 0) {
|
|
detail::heapsort(range, compare);
|
|
return;
|
|
}
|
|
swap(range[range.size() / 2], range.back());
|
|
range_size_t<R> pi = 0;
|
|
R pr = range;
|
|
pr.pop_back();
|
|
for (; !pr.empty(); pr.pop_front()) {
|
|
if (compare(pr.front(), range.back())) {
|
|
swap(pr.front(), range[pi++]);
|
|
}
|
|
}
|
|
swap(range[pi], range.back());
|
|
detail::introloop(range.slice(0, pi), compare, depth - 1);
|
|
detail::introloop(range.slice(pi + 1), compare, depth - 1);
|
|
}
|
|
|
|
template<typename R, typename C>
|
|
inline void introsort(R range, C &compare) {
|
|
detail::introloop(
|
|
range, compare,
|
|
static_cast<range_size_t<R>>(2 * (log(range.size()) / log(2)))
|
|
);
|
|
}
|
|
} /* namespace detail */
|
|
|
|
template<typename R, typename C>
|
|
inline R sort_cmp(R range, C compare) {
|
|
detail::introsort(range, compare);
|
|
return range;
|
|
}
|
|
template<typename C>
|
|
inline auto sort_cmp(C &&compare) {
|
|
return [compare = std::forward<C>(compare)](auto &&obj) mutable {
|
|
return sort_cmp(
|
|
std::forward<decltype(obj)>(obj), std::forward<C>(compare)
|
|
);
|
|
};
|
|
}
|
|
|
|
template<typename R>
|
|
inline R sort(R range) {
|
|
return sort_cmp(range, std::less<range_value_t<R>>());
|
|
}
|
|
inline auto sort() {
|
|
return [](auto &&obj) { return sort(std::forward<decltype(obj)>(obj)); };
|
|
}
|
|
|
|
/* min/max(_element) */
|
|
|
|
template<typename R>
|
|
inline R min_element(R range) {
|
|
R r = range;
|
|
for (; !range.empty(); range.pop_front()) {
|
|
if (std::min(r.front(), range.front()) == range.front()) {
|
|
r = range;
|
|
}
|
|
}
|
|
return r;
|
|
}
|
|
template<typename R, typename C>
|
|
inline R min_element_cmp(R range, C compare) {
|
|
R r = range;
|
|
for (; !range.empty(); range.pop_front()) {
|
|
if (std::min(r.front(), range.front(), compare) == range.front()) {
|
|
r = range;
|
|
}
|
|
}
|
|
return r;
|
|
}
|
|
inline auto min_element() {
|
|
return [](auto &&obj) {
|
|
return min_element(std::forward<decltype(obj)>(obj));
|
|
};
|
|
}
|
|
template<typename C>
|
|
inline auto min_element_cmp(C &&compare) {
|
|
return [compare = std::forward<C>(compare)](auto &&obj) mutable {
|
|
return min_element_cmp(
|
|
std::forward<decltype(obj)>(obj), std::forward<C>(compare)
|
|
);
|
|
};
|
|
}
|
|
|
|
template<typename R>
|
|
inline R max_element(R range) {
|
|
R r = range;
|
|
for (; !range.empty(); range.pop_front()) {
|
|
if (std::max(r.front(), range.front()) == range.front()) {
|
|
r = range;
|
|
}
|
|
}
|
|
return r;
|
|
}
|
|
template<typename R, typename C>
|
|
inline R max_element_cmp(R range, C compare) {
|
|
R r = range;
|
|
for (; !range.empty(); range.pop_front()) {
|
|
if (std::max(r.front(), range.front(), compare) == range.front()) {
|
|
r = range;
|
|
}
|
|
}
|
|
return r;
|
|
}
|
|
inline auto max_element() {
|
|
return [](auto &&obj) {
|
|
return max_element(std::forward<decltype(obj)>(obj));
|
|
};
|
|
}
|
|
template<typename C>
|
|
inline auto max_element_cmp(C &&compare) {
|
|
return [compare = std::forward<C>(compare)](auto &&obj) mutable {
|
|
return max_element_cmp(
|
|
std::forward<decltype(obj)>(obj), std::forward<C>(compare)
|
|
);
|
|
};
|
|
}
|
|
|
|
/* lexicographical compare */
|
|
|
|
template<typename R1, typename R2>
|
|
inline bool lexicographical_compare(R1 range1, R2 range2) {
|
|
while (!range1.empty() && !range2.empty()) {
|
|
if (range1.front() < range2.front()) {
|
|
return true;
|
|
}
|
|
if (range2.front() < range1.front()) {
|
|
return false;
|
|
}
|
|
range1.pop_front();
|
|
range2.pop_front();
|
|
}
|
|
return (range1.empty() && !range2.empty());
|
|
}
|
|
template<typename R>
|
|
inline auto lexicographical_compare(R &&range) {
|
|
return [range = std::forward<R>(range)](auto &&obj) mutable {
|
|
return lexicographical_compare(
|
|
std::forward<decltype(obj)>(obj), std::forward<R>(range)
|
|
);
|
|
};
|
|
}
|
|
|
|
template<typename R1, typename R2, typename C>
|
|
inline bool lexicographical_compare_cmp(R1 range1, R2 range2, C compare) {
|
|
while (!range1.empty() && !range2.empty()) {
|
|
if (compare(range1.front(), range2.front())) {
|
|
return true;
|
|
}
|
|
if (compare(range2.front(), range1.front())) {
|
|
return false;
|
|
}
|
|
range1.pop_front();
|
|
range2.pop_front();
|
|
}
|
|
return (range1.empty() && !range2.empty());
|
|
}
|
|
template<typename R, typename C>
|
|
inline auto lexicographical_compare_cmp(R &&range, C &&compare) {
|
|
return [
|
|
range = std::forward<R>(range), compare = std::forward<C>(compare)
|
|
](auto &&obj) mutable {
|
|
return lexicographical_compare_cmp(
|
|
std::forward<decltype(obj)>(obj), std::forward<R>(range),
|
|
std::forward<C>(compare)
|
|
);
|
|
};
|
|
}
|
|
|
|
/* algos that don't change the range */
|
|
|
|
template<typename R, typename F>
|
|
inline F for_each(R range, F func) {
|
|
for (; !range.empty(); range.pop_front()) {
|
|
func(range.front());
|
|
}
|
|
return std::move(func);
|
|
}
|
|
|
|
template<typename F>
|
|
inline auto for_each(F &&func) {
|
|
return [func = std::forward<F>(func)](auto &&obj) mutable {
|
|
return for_each(std::forward<decltype(obj)>(obj), std::forward<F>(func));
|
|
};
|
|
}
|
|
|
|
template<typename R, typename P>
|
|
inline bool all_of(R range, P pred) {
|
|
for (; !range.empty(); range.pop_front()) {
|
|
if (!pred(range.front())) {
|
|
return false;
|
|
}
|
|
}
|
|
return true;
|
|
}
|
|
|
|
template<typename F>
|
|
inline auto all_of(F &&func) {
|
|
return [func = std::forward<F>(func)](auto &&obj) mutable {
|
|
return all_of(std::forward<decltype(obj)>(obj), std::forward<F>(func));
|
|
};
|
|
}
|
|
|
|
template<typename R, typename P>
|
|
inline bool any_of(R range, P pred) {
|
|
for (; !range.empty(); range.pop_front())
|
|
if (pred(range.front())) return true;
|
|
return false;
|
|
}
|
|
|
|
template<typename F>
|
|
inline auto any_of(F &&func) {
|
|
return [func = std::forward<F>(func)](auto &&obj) mutable {
|
|
return any_of(std::forward<decltype(obj)>(obj), std::forward<F>(func));
|
|
};
|
|
}
|
|
|
|
template<typename R, typename P>
|
|
inline bool none_of(R range, P pred) {
|
|
for (; !range.empty(); range.pop_front())
|
|
if (pred(range.front())) return false;
|
|
return true;
|
|
}
|
|
|
|
template<typename F>
|
|
inline auto none_of(F &&func) {
|
|
return [func = std::forward<F>(func)](auto &&obj) mutable {
|
|
return none_of(std::forward<decltype(obj)>(obj), std::forward<F>(func));
|
|
};
|
|
}
|
|
|
|
template<typename R, typename T>
|
|
inline R find(R range, T const &v) {
|
|
for (; !range.empty(); range.pop_front()) {
|
|
if (range.front() == v) {
|
|
break;
|
|
}
|
|
}
|
|
return range;
|
|
}
|
|
|
|
template<typename T>
|
|
inline auto find(T &&v) {
|
|
return [v = std::forward<T>(v)](auto &&obj) mutable {
|
|
return find(std::forward<decltype(obj)>(obj), std::forward<T>(v));
|
|
};
|
|
}
|
|
|
|
template<typename R, typename T>
|
|
inline R find_last(R range, T const &v) {
|
|
range = find(range, v);
|
|
if (!range.empty()) {
|
|
for (;;) {
|
|
R prev = range;
|
|
prev.pop_front();
|
|
R r = find(prev, v);
|
|
if (r.empty()) {
|
|
break;
|
|
}
|
|
range = r;
|
|
}
|
|
}
|
|
return range;
|
|
}
|
|
|
|
template<typename T>
|
|
inline auto find_last(T &&v) {
|
|
return [v = std::forward<T>(v)](auto &&obj) mutable {
|
|
return find_last(std::forward<decltype(obj)>(obj), std::forward<T>(v));
|
|
};
|
|
}
|
|
|
|
template<typename R, typename P>
|
|
inline R find_if(R range, P pred) {
|
|
for (; !range.empty(); range.pop_front()) {
|
|
if (pred(range.front())) {
|
|
break;
|
|
}
|
|
}
|
|
return range;
|
|
}
|
|
|
|
template<typename F>
|
|
inline auto find_if(F &&func) {
|
|
return [func = std::forward<F>(func)](auto &&obj) mutable {
|
|
return find_if(std::forward<decltype(obj)>(obj), std::forward<F>(func));
|
|
};
|
|
}
|
|
|
|
template<typename R, typename P>
|
|
inline R find_if_not(R range, P pred) {
|
|
for (; !range.empty(); range.pop_front()) {
|
|
if (!pred(range.front())) {
|
|
break;
|
|
}
|
|
}
|
|
return range;
|
|
}
|
|
|
|
template<typename F>
|
|
inline auto find_if_not(F &&func) {
|
|
return [func = std::forward<F>(func)](auto &&obj) mutable {
|
|
return find_if_not(
|
|
std::forward<decltype(obj)>(obj), std::forward<F>(func)
|
|
);
|
|
};
|
|
}
|
|
|
|
template<typename R1, typename R2, typename C>
|
|
inline R1 find_one_of_cmp(R1 range, R2 values, C compare) {
|
|
for (; !range.empty(); range.pop_front()) {
|
|
for (R2 rv = values; !rv.empty(); rv.pop_front()) {
|
|
if (compare(range.front(), rv.front())) {
|
|
return range;
|
|
}
|
|
}
|
|
}
|
|
return range;
|
|
}
|
|
template<typename R, typename C>
|
|
inline auto find_one_of_cmp(R &&values, C &&compare) {
|
|
return [
|
|
values = std::forward<R>(values), compare = std::forward<C>(compare)
|
|
](auto &&obj) mutable {
|
|
return find_one_of_cmp(
|
|
std::forward<decltype(obj)>(obj), std::forward<R>(values),
|
|
std::forward<C>(compare)
|
|
);
|
|
};
|
|
}
|
|
|
|
template<typename R1, typename R2>
|
|
inline R1 find_one_of(R1 range, R2 values) {
|
|
for (; !range.empty(); range.pop_front()) {
|
|
for (R2 rv = values; !rv.empty(); rv.pop_front()) {
|
|
if (range.front() == rv.front()) {
|
|
return range;
|
|
}
|
|
}
|
|
}
|
|
return range;
|
|
}
|
|
template<typename R>
|
|
inline auto find_one_of(R &&values) {
|
|
return [values = std::forward<R>(values)](auto &&obj) mutable {
|
|
return find_one_of(
|
|
std::forward<decltype(obj)>(obj), std::forward<R>(values)
|
|
);
|
|
};
|
|
}
|
|
|
|
template<typename R, typename T>
|
|
inline range_size_t<R> count(R range, T const &v) {
|
|
range_size_t<R> ret = 0;
|
|
for (; !range.empty(); range.pop_front()) {
|
|
if (range.front() == v) {
|
|
++ret;
|
|
}
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
template<typename T>
|
|
inline auto count(T &&v) {
|
|
return [v = std::forward<T>(v)](auto &&obj) mutable {
|
|
return count(std::forward<decltype(obj)>(obj), std::forward<T>(v));
|
|
};
|
|
}
|
|
|
|
template<typename R, typename P>
|
|
inline range_size_t<R> count_if(R range, P pred) {
|
|
range_size_t<R> ret = 0;
|
|
for (; !range.empty(); range.pop_front()) {
|
|
if (pred(range.front())) {
|
|
++ret;
|
|
}
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
template<typename F>
|
|
inline auto count_if(F &&func) {
|
|
return [func = std::forward<F>(func)](auto &&obj) mutable {
|
|
return count_if(std::forward<decltype(obj)>(obj), std::forward<F>(func));
|
|
};
|
|
}
|
|
|
|
template<typename R, typename P>
|
|
inline range_size_t<R> count_if_not(R range, P pred) {
|
|
range_size_t<R> ret = 0;
|
|
for (; !range.empty(); range.pop_front()) {
|
|
if (!pred(range.front())) {
|
|
++ret;
|
|
}
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
template<typename F>
|
|
inline auto count_if_not(F &&func) {
|
|
return [func = std::forward<F>(func)](auto &&obj) mutable {
|
|
return count_if_not(
|
|
std::forward<decltype(obj)>(obj), std::forward<F>(func)
|
|
);
|
|
};
|
|
}
|
|
|
|
template<typename R>
|
|
inline bool equal(R range1, R range2) {
|
|
for (; !range1.empty(); range1.pop_front()) {
|
|
if (range2.empty() || (range1.front() != range2.front())) {
|
|
return false;
|
|
}
|
|
range2.pop_front();
|
|
}
|
|
return range2.empty();
|
|
}
|
|
|
|
template<typename R>
|
|
inline auto equal(R &&range) {
|
|
return [range = std::forward<R>(range)](auto &&obj) mutable {
|
|
return equal(std::forward<decltype(obj)>(obj), std::forward<R>(range));
|
|
};
|
|
}
|
|
|
|
/* algos that modify ranges or work with output ranges */
|
|
|
|
template<typename R1, typename R2>
|
|
inline R2 copy(R1 irange, R2 orange) {
|
|
range_put_all(orange, irange);
|
|
return orange;
|
|
}
|
|
|
|
template<typename R1, typename R2, typename P>
|
|
inline R2 copy_if(R1 irange, R2 orange, P pred) {
|
|
for (; !irange.empty(); irange.pop_front()) {
|
|
if (pred(irange.front())) {
|
|
orange.put(irange.front());
|
|
}
|
|
}
|
|
return orange;
|
|
}
|
|
|
|
template<typename R1, typename R2, typename P>
|
|
inline R2 copy_if_not(R1 irange, R2 orange, P pred) {
|
|
for (; !irange.empty(); irange.pop_front()) {
|
|
if (!pred(irange.front())) {
|
|
orange.put(irange.front());
|
|
}
|
|
}
|
|
return orange;
|
|
}
|
|
|
|
template<typename R1, typename R2>
|
|
inline R2 move(R1 irange, R2 orange) {
|
|
for (; !irange.empty(); irange.pop_front()) {
|
|
orange.put(std::move(irange.front()));
|
|
}
|
|
return orange;
|
|
}
|
|
|
|
template<typename R>
|
|
inline void reverse(R range) {
|
|
while (!range.empty()) {
|
|
using std::swap;
|
|
swap(range.front(), range.back());
|
|
range.pop_front();
|
|
range.pop_back();
|
|
}
|
|
}
|
|
|
|
template<typename R1, typename R2>
|
|
inline R2 reverse_copy(R1 irange, R2 orange) {
|
|
for (; !irange.empty(); irange.pop_back()) {
|
|
orange.put(irange.back());
|
|
}
|
|
return orange;
|
|
}
|
|
|
|
template<typename R, typename T>
|
|
inline void fill(R range, T const &v) {
|
|
for (; !range.empty(); range.pop_front()) {
|
|
range.front() = v;
|
|
}
|
|
}
|
|
|
|
template<typename R, typename F>
|
|
inline void generate(R range, F gen) {
|
|
for (; !range.empty(); range.pop_front()) {
|
|
range.front() = gen();
|
|
}
|
|
}
|
|
|
|
template<typename R1, typename R2>
|
|
inline std::pair<R1, R2> swap_ranges(R1 range1, R2 range2) {
|
|
while (!range1.empty() && !range2.empty()) {
|
|
using std::swap;
|
|
swap(range1.front(), range2.front());
|
|
range1.pop_front();
|
|
range2.pop_front();
|
|
}
|
|
return std::make_pair(range1, range2);
|
|
}
|
|
|
|
template<typename R, typename T>
|
|
inline void iota(R range, T value) {
|
|
for (; !range.empty(); range.pop_front()) {
|
|
range.front() = value++;
|
|
}
|
|
}
|
|
|
|
template<typename R, typename T>
|
|
inline T foldl(R range, T init) {
|
|
for (; !range.empty(); range.pop_front()) {
|
|
init = init + range.front();
|
|
}
|
|
return init;
|
|
}
|
|
|
|
template<typename R, typename T, typename F>
|
|
inline T foldl_f(R range, T init, F func) {
|
|
for (; !range.empty(); range.pop_front()) {
|
|
init = func(init, range.front());
|
|
}
|
|
return init;
|
|
}
|
|
|
|
template<typename T>
|
|
inline auto foldl(T &&init) {
|
|
return [init = std::forward<T>(init)](auto &&obj) mutable {
|
|
return foldl(std::forward<decltype(obj)>(obj), std::forward<T>(init));
|
|
};
|
|
}
|
|
template<typename T, typename F>
|
|
inline auto foldl_f(T &&init, F &&func) {
|
|
return [
|
|
init = std::forward<T>(init), func = std::forward<F>(func)
|
|
](auto &&obj) mutable {
|
|
return foldl_f(
|
|
std::forward<decltype(obj)>(obj), std::forward<T>(init),
|
|
std::forward<F>(func)
|
|
);
|
|
};
|
|
}
|
|
|
|
template<typename R, typename T>
|
|
inline T foldr(R range, T init) {
|
|
for (; !range.empty(); range.pop_back()) {
|
|
init = init + range.back();
|
|
}
|
|
return init;
|
|
}
|
|
|
|
template<typename R, typename T, typename F>
|
|
inline T foldr_f(R range, T init, F func) {
|
|
for (; !range.empty(); range.pop_back()) {
|
|
init = func(init, range.back());
|
|
}
|
|
return init;
|
|
}
|
|
|
|
template<typename T>
|
|
inline auto foldr(T &&init) {
|
|
return [init = std::forward<T>(init)](auto &&obj) mutable {
|
|
return foldr(std::forward<decltype(obj)>(obj), std::forward<T>(init));
|
|
};
|
|
}
|
|
template<typename T, typename F>
|
|
inline auto foldr_f(T &&init, F &&func) {
|
|
return [
|
|
init = std::forward<T>(init), func = std::forward<F>(func)
|
|
](auto &&obj) mutable {
|
|
return foldr_f(
|
|
std::forward<decltype(obj)>(obj), std::forward<T>(init),
|
|
std::forward<F>(func)
|
|
);
|
|
};
|
|
}
|
|
|
|
template<typename T, typename F, typename R>
|
|
struct map_range: input_range<map_range<T, F, R>> {
|
|
using range_category = std::common_type_t<
|
|
range_category_t<T>, finite_random_access_range_tag
|
|
>;
|
|
using value_type = R;
|
|
using reference = R;
|
|
using size_type = range_size_t<T>;
|
|
using difference_type = range_difference_t<T>;
|
|
|
|
private:
|
|
T p_range;
|
|
std::decay_t<F> p_func;
|
|
|
|
public:
|
|
map_range() = delete;
|
|
template<typename FF>
|
|
map_range(T const &range, FF &&func):
|
|
p_range(range), p_func(std::forward<FF>(func)) {}
|
|
map_range(map_range const &it):
|
|
p_range(it.p_range), p_func(it.p_func) {}
|
|
map_range(map_range &&it):
|
|
p_range(std::move(it.p_range)), p_func(std::move(it.p_func)) {}
|
|
|
|
map_range &operator=(map_range const &v) {
|
|
p_range = v.p_range;
|
|
p_func = v.p_func;
|
|
return *this;
|
|
}
|
|
map_range &operator=(map_range &&v) {
|
|
p_range = std::move(v.p_range);
|
|
p_func = std::move(v.p_func);
|
|
return *this;
|
|
}
|
|
|
|
bool empty() const { return p_range.empty(); }
|
|
size_type size() const { return p_range.size(); }
|
|
|
|
void pop_front() { p_range.pop_front(); }
|
|
void pop_back() { p_range.pop_back(); }
|
|
|
|
R front() const { return p_func(p_range.front()); }
|
|
R back() const { return p_func(p_range.back()); }
|
|
|
|
R operator[](size_type idx) const {
|
|
return p_func(p_range[idx]);
|
|
}
|
|
|
|
map_range slice(size_type start, size_type end) const {
|
|
return map_range(p_range.slice(start, end), p_func);
|
|
}
|
|
map_range slice(size_type start) const {
|
|
return slice(start, size());
|
|
}
|
|
};
|
|
|
|
namespace detail {
|
|
template<typename R, typename F>
|
|
using MapReturnType = decltype(
|
|
std::declval<F>()(std::declval<range_reference_t<R>>())
|
|
);
|
|
}
|
|
|
|
template<typename R, typename F>
|
|
inline map_range<R, F, detail::MapReturnType<R, F>> map(R range, F func) {
|
|
return map_range<R, F, detail::MapReturnType<R, F>>(range, std::move(func));
|
|
}
|
|
|
|
template<typename F>
|
|
inline auto map(F &&func) {
|
|
return [func = std::forward<F>(func)](auto &&obj) mutable {
|
|
return map(std::forward<decltype(obj)>(obj), std::forward<F>(func));
|
|
};
|
|
}
|
|
|
|
template<typename T, typename F>
|
|
struct filter_range: input_range<filter_range<T, F>> {
|
|
using range_category = std::common_type_t<
|
|
range_category_t<T>, forward_range_tag
|
|
>;
|
|
using value_type = range_value_t<T>;
|
|
using reference = range_reference_t<T>;
|
|
using size_type = range_size_t<T>;
|
|
using difference_type = range_difference_t<T>;
|
|
|
|
private:
|
|
T p_range;
|
|
std::decay_t<F> p_pred;
|
|
|
|
void advance_valid() {
|
|
while (!p_range.empty() && !p_pred(front())) {
|
|
p_range.pop_front();
|
|
}
|
|
}
|
|
|
|
public:
|
|
filter_range() = delete;
|
|
template<typename P>
|
|
filter_range(T const &range, P &&pred):
|
|
p_range(range), p_pred(std::forward<P>(pred))
|
|
{
|
|
advance_valid();
|
|
}
|
|
filter_range(filter_range const &it):
|
|
p_range(it.p_range), p_pred(it.p_pred)
|
|
{
|
|
advance_valid();
|
|
}
|
|
filter_range(filter_range &&it):
|
|
p_range(std::move(it.p_range)), p_pred(std::move(it.p_pred))
|
|
{
|
|
advance_valid();
|
|
}
|
|
|
|
filter_range &operator=(filter_range const &v) {
|
|
p_range = v.p_range;
|
|
p_pred = v.p_pred;
|
|
advance_valid();
|
|
return *this;
|
|
}
|
|
filter_range &operator=(filter_range &&v) {
|
|
p_range = std::move(v.p_range);
|
|
p_pred = std::move(v.p_pred);
|
|
advance_valid();
|
|
return *this;
|
|
}
|
|
|
|
bool empty() const { return p_range.empty(); }
|
|
|
|
void pop_front() {
|
|
p_range.pop_front();
|
|
advance_valid();
|
|
}
|
|
|
|
range_reference_t<T> front() const { return p_range.front(); }
|
|
};
|
|
|
|
namespace detail {
|
|
template<typename R, typename P>
|
|
using FilterPred = std::enable_if_t<std::is_same_v<
|
|
decltype(std::declval<P>()(std::declval<range_reference_t<R>>())), bool
|
|
>, P>;
|
|
}
|
|
|
|
template<typename R, typename P>
|
|
inline filter_range<R, detail::FilterPred<R, P>> filter(R range, P pred) {
|
|
return filter_range<R, P>(range, std::move(pred));
|
|
}
|
|
|
|
template<typename F>
|
|
inline auto filter(F &&func) {
|
|
return [func = std::forward<F>(func)](auto &&obj) mutable {
|
|
return filter(std::forward<decltype(obj)>(obj), std::forward<F>(func));
|
|
};
|
|
}
|
|
|
|
} /* namespace ostd */
|
|
|
|
#endif
|