Utility/Ruby.cpp

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• Last update: 2021-03-26 12:00:51+09:00

Required by

• template.cpp

Verified with

• test/IO_2Dvector_and_Ruby_push_back_Transpose_Map_Sum.test.cpp
• test/IO_vector_and_Ruby_Reverse.test.cpp
• test/Ruby_Min_Max_Sum.test.cpp
• test/template.test.cpp
• test/template_no_Ruby.test.cpp

Code

#pragma once
#include <vector>
#include <string>
#include <map>
#include <algorithm>
#include <numeric>
#include <cassert>
#include <iostream>

template <class F> struct Callable {
	F func;
	Callable(const F& f) : func(f) {}
};
template <class T, class F> auto operator|(const T& v, const Callable<F>& c) {
	return c.func(v);
}

struct Sort_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			std::sort(std::begin(v), std::end(v), f);
			return v;
		});
	}
	template <class T> friend auto operator|(T v, [[maybe_unused]] const Sort_impl& c) {
		std::sort(std::begin(v), std::end(v));
		return v;
	}
} Sort;
struct SortBy_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			std::sort(std::begin(v), std::end(v),
			          [&](const auto& i, const auto& j) { return f(i) < f(j); });
			return v;
		});
	}
} SortBy;
struct RSort_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			std::sort(rbegin(v), rend(v), f);
			return v;
		});
	}
	template <class T> friend auto operator|(T v, [[maybe_unused]] const RSort_impl& c) {
		std::sort(rbegin(v), rend(v));
		return v;
	}
} RSort;
struct RSortBy_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			std::sort(std::begin(v), std::end(v),
			          [&](const auto& i, const auto& j) { return f(i) > f(j); });
			return v;
		});
	}
} RSortBy;
struct Reverse_impl {
	template <class T> friend auto operator|(T v, const Reverse_impl& c) {
		std::reverse(std::begin(v), std::end(v));
		return v;
	}
} Reverse;
struct Unique_impl {
	template <class T> friend auto operator|(T v, const Unique_impl& c) {
		v.erase(std::unique(std::begin(v), std::end(v), std::end(v)));
		return v;
	}
	template <class T, class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			v.erase(std::unique(std::begin(v), std::end(v), f), std::end(v));
			return v;
		});
	}
} Unique;
struct Uniq_impl {
	template <class T> friend auto operator|(T v, const Uniq_impl& c) {
		std::sort(std::begin(v), std::end(v));
		v.erase(std::unique(std::begin(v), std::end(v)), std::end(v));
		return v;
	}
} Uniq;
struct Rotate_impl {
	auto operator()(int&& left) {
		return Callable([&](auto v) {
			int s = static_cast<int>(std::size(v));
			assert(-s <= left && left <= s);
			if (0 <= left) {
				std::rotate(std::begin(v), std::begin(v) + left, std::end(v));
			} else {
				std::rotate(std::begin(v), std::end(v) + left, std::end(v));
			}
			return v;
		});
	}
} Rotate;
struct Max_impl {
	template <class F> auto operator()(F&& f) {
		return Callable(
		    [&](auto v) { return *std::max_element(std::begin(v), std::end(v), f); });
	}
	template <class T> friend auto operator|(T v, const Max_impl& c) {
		return *std::max_element(std::begin(v), std::end(v));
	}
} Max;
struct Min_impl {
	template <class F> auto operator()(F&& f) {
		return Callable(
		    [&](auto v) { return *std::min_element(std::begin(v), std::end(v), f); });
	}
	template <class T> friend auto operator|(T v, const Min_impl& c) {
		return *std::min_element(std::begin(v), std::end(v));
	}
} Min;
struct MaxPos_impl {
	template <class T> friend auto operator|(T v, const MaxPos_impl& c) {
		return std::max_element(std::begin(v), std::end(v)) - std::begin(v);
	}
} MaxPos;
struct MinPos_impl {
	template <class T> friend auto operator|(T v, const MinPos_impl& c) {
		return std::min_element(std::begin(v), std::end(v)) - std::begin(v);
	}
} MinPos;
struct MaxBy_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			auto max_it = std::begin(v);
			auto max_val = f(*max_it);
			for (auto it = std::next(std::begin(v)); it != std::end(v); ++it) {
				if (auto val = f(*it); max_val < val) {
					max_it = it;
					max_val = val;
				}
			}
			return *max_it;
		});
	}
} MaxBy;
struct MinBy_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			auto min_it = std::begin(v);
			auto min_val = f(*min_it);
			for (auto it = std::next(std::begin(v)); it != std::end(v); ++it) {
				if (auto val = f(*it); min_val > val) {
					min_it = it;
					min_val = val;
				}
			}
			return *min_it;
		});
	}
} MinBy;
struct MaxOf_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			auto max_val = f(*std::begin(v));
			for (auto it = std::next(std::begin(v)); it != std::end(v); ++it) {
				if (auto val = f(*it); max_val < val) {
					max_val = val;
				}
			}
			return max_val;
		});
	}
} MaxOf;
struct MinOf_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			auto min_val = f(*std::begin(v));
			for (auto it = std::next(std::begin(v)); it != std::end(v); ++it) {
				if (auto val = f(*it); min_val > val) {
					min_val = val;
				}
			}
			return min_val;
		});
	}
} MinOf;
struct Count_impl {
	template <class V> auto operator()(const V& val) {
		return Callable([&](auto v) { return std::count(std::begin(v), std::end(v), val); });
	}
} Count;
struct CountIf_impl {
	template <class F> auto operator()(const F& f) {
		return Callable([&](auto v) { return std::count_if(std::begin(v), std::end(v), f); });
	}
} CountIf;
struct Index_impl {
	template <class V> auto operator()(const V& val) {
		return Callable([&](auto v) -> std::optional<int> {
			auto result = std::find(std::begin(v), std::end(v), val);
			return result != std::end(v) ? std::optional(result - std::begin(v))
			                             : std::nullopt;
		});
	}
	template <class V> auto operator()(const V& val, std::size_t i) {
		return Callable([&](auto v) -> std::optional<int> {
			auto result = std::find(std::next(std::begin(v), i), std::end(v), val);
			return result != std::end(v) ? std::optional(result - std::begin(v))
			                             : std::nullopt;
		});
	}
} Index;
struct IndexIf_impl {
	template <class F> auto operator()(const F& f) {
		return Callable([&](auto v) -> std::optional<int> {
			auto result = std::find_if(std::begin(v), std::end(v), f);
			return result != std::end(v) ? std::optional(result - std::begin(v))
			                             : std::nullopt;
		});
	}
} IndexIf;
struct FindIf_impl {
	template <class F> auto operator()(const F& f) {
		return Callable([&](auto v) -> std::optional<typename decltype(v)::value_type> {
			auto result = std::find_if(std::begin(v), std::end(v), f);
			return result != std::end(v) ? std::optional(*result) : std::nullopt;
		});
	}
} FindIf;
struct Sum_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			return std::accumulate(std::next(std::begin(v)), std::end(v), f(*std::begin(v)),
			                       [&](const auto& a, const auto& b) { return a + f(b); });
		});
	}
	template <class T> friend auto operator|(T v, [[maybe_unused]] const Sum_impl& c) {
		return std::accumulate(std::begin(v), std::end(v), typename T::value_type{});
	}
} Sum;
struct Includes {
	template <class V> auto operator()(const V& val) {
		return Callable(
		    [&](auto v) { return std::find(std::begin(v), std::end(v), val) != std::end(v); });
	}
} Includes;
struct IncludesIf_impl {
	template <class F> auto operator()(const F& f) {
		return Callable([&](auto v) {
			return std::find_if(std::begin(v), std::end(v), f) != std::end(v);
		});
	}
} IncludesIf;
struct RemoveIf_impl {
	template <class F> auto operator()(const F& f) {
		return Callable([&](auto v) {
			v.erase(std::remove_if(std::begin(v), std::end(v), f), std::end(v));
			return v;
		});
	}
} RemoveIf;
struct Each_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			for (const auto& i : v) {
				f(i);
			}
		});
	}
} Each;
struct EachConsPair_impl {
	template <class T, class value_type = typename T::value_type>
	friend auto operator|(const T& v, EachConsPair_impl& c) {
		std::vector<std::pair<value_type, value_type>> result;
		if (std::size(v) >= 2) {
			result.reserve(std::size(v) - 1);
			for (std::size_t i = 0; i < std::size(v) - 1; ++i) {
				result.emplace_back(v[i], v[i + 1]);
			}
		}
		return result;
	}
} EachConsPair;
struct Select_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			using value_type = typename decltype(v)::value_type;
			std::vector<value_type> result;
			for (const auto& i : v) {
				if (f(i)) result.push_back(i);
			}
			return result;
		});
	}
} Select;
struct Map_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			using result_type = std::invoke_result_t<F, typename decltype(v)::value_type>;
			std::vector<result_type> result;
			result.reserve(std::size(v));
			for (const auto& i : v) {
				result.push_back(f(i));
			}
			return result;
		});
	}
} Map;
struct Indexed_impl {
	template <class T> friend auto operator|(const T& v, Indexed_impl& c) {
		using value_type = typename T::value_type;
		std::vector<std::pair<value_type, int>> result;
		result.reserve(std::size(v));
		int index = 0;
		for (const auto& i : v) {
			result.emplace_back(i, index++);
		}
		return result;
	}
} Indexed;
struct AllOf_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			for (const auto& i : v) {
				if (!f(i)) return false;
			}
			return true;
		});
	}
} AllOf;
struct AnyOf_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			for (const auto& i : v) {
				if (f(i)) return true;
			}
			return false;
		});
	}
} AnyOf;
struct NoneOf_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			for (const auto& i : v) {
				if (f(i)) return false;
			}
			return true;
		});
	}
} NoneOf;

struct Tally_impl {
	auto operator()(std::size_t max_val) {
		return Callable([&](auto v) {
			std::vector<std::size_t> result(max_val);
			for (const auto& i : v) {
				result[static_cast<std::size_t>(i)]++;
			}
			return result;
		});
	}
	template <class T, class value_type = typename T::value_type>
	friend auto operator|(const T& v, Tally_impl& c) {
		std::map<value_type, std::size_t> result;
		for (const auto& i : v) {
			result[i]++;
		}
		return result;
	}
} Tally;

struct Reduce_impl {
	template <class T, class F> auto operator()(T memo, F f) {
		return Callable([memo, f](auto v) {
			auto acc = memo;
			for (auto i : v) {
				acc = f(acc, i);
			}
			return acc;
		});
	}
} Reduce;

struct Join_impl {
	auto operator()(std::string separater) {
		return Callable([&](auto v) {
			std::string result;
			bool first = true;
			for (const auto& i : v) {
				if (!std::exchange(first, false)) {
					result += separater;
				}
				result += std::to_string(i);
			}
			return result;
		});
	}
	template <class T> friend auto operator|(const T& v, Join_impl& c) {
		return v | c("");
	}
} Join;

struct At_impl {
	auto operator()(std::size_t l, std::size_t r) {
		return Callable(
		    [l, r](auto v) { return decltype(v)(std::begin(v) + l, std::begin(v) + r); });
	}
} At;
struct Slice_impl {
	auto operator()(std::size_t i, std::size_t cnt) {
		return Callable([i, cnt](auto v) {
			return decltype(v)(std::begin(v) + i, std::begin(v) + i + cnt);
		});
	}
} Slice;

struct Transpose_impl {
	template <class T>
	friend auto operator|(const std::vector<std::vector<T>>& v, Transpose_impl& c) {
		std::size_t h = v.size(), w = v.front().size();
		std::vector result(w, std::vector<T>(h));
		for (std::size_t i = 0; i < h; ++i) {
			assert(v[i].size() == w);
			for (std::size_t j = 0; j < w; ++j) {
				result[j][i] = v[i][j];
			}
		}
		return result;
	}
} Transpose;

template <class T> auto operator*(const std::vector<T>& a, std::size_t n) {
	T result;
	for (std::size_t i = 0; i < n; ++i) {
		result.insert(result.end(), a.begin(), a.end());
	}
	return result;
}
auto operator*(std::string a, std::size_t n) {
	std::string result;
	for (std::size_t i = 0; i < n; ++i) {
		result += a;
	}
	return result;
}

namespace internal {
	template <class T, class U, class = void> struct has_push_back : std::false_type {};
	template <class T, class U>
	struct has_push_back<T, U,
	                     std::void_t<decltype(std::declval<T>().push_back(std::declval<U>()))>>
	    : std::true_type {};
}  // namespace internal
template <
    class Container, class T,
    std::enable_if_t<internal::has_push_back<Container, T>::value, std::nullptr_t> = nullptr>
auto& operator<<(Container& continer, const T& val) {
	continer.push_back(val);
	return continer;
}
template <
    class Container, class T,
    std::enable_if_t<internal::has_push_back<Container, T>::value, std::nullptr_t> = nullptr>
auto operator+(Container continer, const T& val) {
	continer << val;
	return continer;
}

#line 2 "Utility/Ruby.cpp"
#include <vector>
#include <string>
#include <map>
#include <algorithm>
#include <numeric>
#include <cassert>
#include <iostream>

template <class F> struct Callable {
	F func;
	Callable(const F& f) : func(f) {}
};
template <class T, class F> auto operator|(const T& v, const Callable<F>& c) {
	return c.func(v);
}

struct Sort_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			std::sort(std::begin(v), std::end(v), f);
			return v;
		});
	}
	template <class T> friend auto operator|(T v, [[maybe_unused]] const Sort_impl& c) {
		std::sort(std::begin(v), std::end(v));
		return v;
	}
} Sort;
struct SortBy_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			std::sort(std::begin(v), std::end(v),
			          [&](const auto& i, const auto& j) { return f(i) < f(j); });
			return v;
		});
	}
} SortBy;
struct RSort_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			std::sort(rbegin(v), rend(v), f);
			return v;
		});
	}
	template <class T> friend auto operator|(T v, [[maybe_unused]] const RSort_impl& c) {
		std::sort(rbegin(v), rend(v));
		return v;
	}
} RSort;
struct RSortBy_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			std::sort(std::begin(v), std::end(v),
			          [&](const auto& i, const auto& j) { return f(i) > f(j); });
			return v;
		});
	}
} RSortBy;
struct Reverse_impl {
	template <class T> friend auto operator|(T v, const Reverse_impl& c) {
		std::reverse(std::begin(v), std::end(v));
		return v;
	}
} Reverse;
struct Unique_impl {
	template <class T> friend auto operator|(T v, const Unique_impl& c) {
		v.erase(std::unique(std::begin(v), std::end(v), std::end(v)));
		return v;
	}
	template <class T, class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			v.erase(std::unique(std::begin(v), std::end(v), f), std::end(v));
			return v;
		});
	}
} Unique;
struct Uniq_impl {
	template <class T> friend auto operator|(T v, const Uniq_impl& c) {
		std::sort(std::begin(v), std::end(v));
		v.erase(std::unique(std::begin(v), std::end(v)), std::end(v));
		return v;
	}
} Uniq;
struct Rotate_impl {
	auto operator()(int&& left) {
		return Callable([&](auto v) {
			int s = static_cast<int>(std::size(v));
			assert(-s <= left && left <= s);
			if (0 <= left) {
				std::rotate(std::begin(v), std::begin(v) + left, std::end(v));
			} else {
				std::rotate(std::begin(v), std::end(v) + left, std::end(v));
			}
			return v;
		});
	}
} Rotate;
struct Max_impl {
	template <class F> auto operator()(F&& f) {
		return Callable(
		    [&](auto v) { return *std::max_element(std::begin(v), std::end(v), f); });
	}
	template <class T> friend auto operator|(T v, const Max_impl& c) {
		return *std::max_element(std::begin(v), std::end(v));
	}
} Max;
struct Min_impl {
	template <class F> auto operator()(F&& f) {
		return Callable(
		    [&](auto v) { return *std::min_element(std::begin(v), std::end(v), f); });
	}
	template <class T> friend auto operator|(T v, const Min_impl& c) {
		return *std::min_element(std::begin(v), std::end(v));
	}
} Min;
struct MaxPos_impl {
	template <class T> friend auto operator|(T v, const MaxPos_impl& c) {
		return std::max_element(std::begin(v), std::end(v)) - std::begin(v);
	}
} MaxPos;
struct MinPos_impl {
	template <class T> friend auto operator|(T v, const MinPos_impl& c) {
		return std::min_element(std::begin(v), std::end(v)) - std::begin(v);
	}
} MinPos;
struct MaxBy_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			auto max_it = std::begin(v);
			auto max_val = f(*max_it);
			for (auto it = std::next(std::begin(v)); it != std::end(v); ++it) {
				if (auto val = f(*it); max_val < val) {
					max_it = it;
					max_val = val;
				}
			}
			return *max_it;
		});
	}
} MaxBy;
struct MinBy_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			auto min_it = std::begin(v);
			auto min_val = f(*min_it);
			for (auto it = std::next(std::begin(v)); it != std::end(v); ++it) {
				if (auto val = f(*it); min_val > val) {
					min_it = it;
					min_val = val;
				}
			}
			return *min_it;
		});
	}
} MinBy;
struct MaxOf_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			auto max_val = f(*std::begin(v));
			for (auto it = std::next(std::begin(v)); it != std::end(v); ++it) {
				if (auto val = f(*it); max_val < val) {
					max_val = val;
				}
			}
			return max_val;
		});
	}
} MaxOf;
struct MinOf_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			auto min_val = f(*std::begin(v));
			for (auto it = std::next(std::begin(v)); it != std::end(v); ++it) {
				if (auto val = f(*it); min_val > val) {
					min_val = val;
				}
			}
			return min_val;
		});
	}
} MinOf;
struct Count_impl {
	template <class V> auto operator()(const V& val) {
		return Callable([&](auto v) { return std::count(std::begin(v), std::end(v), val); });
	}
} Count;
struct CountIf_impl {
	template <class F> auto operator()(const F& f) {
		return Callable([&](auto v) { return std::count_if(std::begin(v), std::end(v), f); });
	}
} CountIf;
struct Index_impl {
	template <class V> auto operator()(const V& val) {
		return Callable([&](auto v) -> std::optional<int> {
			auto result = std::find(std::begin(v), std::end(v), val);
			return result != std::end(v) ? std::optional(result - std::begin(v))
			                             : std::nullopt;
		});
	}
	template <class V> auto operator()(const V& val, std::size_t i) {
		return Callable([&](auto v) -> std::optional<int> {
			auto result = std::find(std::next(std::begin(v), i), std::end(v), val);
			return result != std::end(v) ? std::optional(result - std::begin(v))
			                             : std::nullopt;
		});
	}
} Index;
struct IndexIf_impl {
	template <class F> auto operator()(const F& f) {
		return Callable([&](auto v) -> std::optional<int> {
			auto result = std::find_if(std::begin(v), std::end(v), f);
			return result != std::end(v) ? std::optional(result - std::begin(v))
			                             : std::nullopt;
		});
	}
} IndexIf;
struct FindIf_impl {
	template <class F> auto operator()(const F& f) {
		return Callable([&](auto v) -> std::optional<typename decltype(v)::value_type> {
			auto result = std::find_if(std::begin(v), std::end(v), f);
			return result != std::end(v) ? std::optional(*result) : std::nullopt;
		});
	}
} FindIf;
struct Sum_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			return std::accumulate(std::next(std::begin(v)), std::end(v), f(*std::begin(v)),
			                       [&](const auto& a, const auto& b) { return a + f(b); });
		});
	}
	template <class T> friend auto operator|(T v, [[maybe_unused]] const Sum_impl& c) {
		return std::accumulate(std::begin(v), std::end(v), typename T::value_type{});
	}
} Sum;
struct Includes {
	template <class V> auto operator()(const V& val) {
		return Callable(
		    [&](auto v) { return std::find(std::begin(v), std::end(v), val) != std::end(v); });
	}
} Includes;
struct IncludesIf_impl {
	template <class F> auto operator()(const F& f) {
		return Callable([&](auto v) {
			return std::find_if(std::begin(v), std::end(v), f) != std::end(v);
		});
	}
} IncludesIf;
struct RemoveIf_impl {
	template <class F> auto operator()(const F& f) {
		return Callable([&](auto v) {
			v.erase(std::remove_if(std::begin(v), std::end(v), f), std::end(v));
			return v;
		});
	}
} RemoveIf;
struct Each_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			for (const auto& i : v) {
				f(i);
			}
		});
	}
} Each;
struct EachConsPair_impl {
	template <class T, class value_type = typename T::value_type>
	friend auto operator|(const T& v, EachConsPair_impl& c) {
		std::vector<std::pair<value_type, value_type>> result;
		if (std::size(v) >= 2) {
			result.reserve(std::size(v) - 1);
			for (std::size_t i = 0; i < std::size(v) - 1; ++i) {
				result.emplace_back(v[i], v[i + 1]);
			}
		}
		return result;
	}
} EachConsPair;
struct Select_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			using value_type = typename decltype(v)::value_type;
			std::vector<value_type> result;
			for (const auto& i : v) {
				if (f(i)) result.push_back(i);
			}
			return result;
		});
	}
} Select;
struct Map_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			using result_type = std::invoke_result_t<F, typename decltype(v)::value_type>;
			std::vector<result_type> result;
			result.reserve(std::size(v));
			for (const auto& i : v) {
				result.push_back(f(i));
			}
			return result;
		});
	}
} Map;
struct Indexed_impl {
	template <class T> friend auto operator|(const T& v, Indexed_impl& c) {
		using value_type = typename T::value_type;
		std::vector<std::pair<value_type, int>> result;
		result.reserve(std::size(v));
		int index = 0;
		for (const auto& i : v) {
			result.emplace_back(i, index++);
		}
		return result;
	}
} Indexed;
struct AllOf_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			for (const auto& i : v) {
				if (!f(i)) return false;
			}
			return true;
		});
	}
} AllOf;
struct AnyOf_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			for (const auto& i : v) {
				if (f(i)) return true;
			}
			return false;
		});
	}
} AnyOf;
struct NoneOf_impl {
	template <class F> auto operator()(F&& f) {
		return Callable([&](auto v) {
			for (const auto& i : v) {
				if (f(i)) return false;
			}
			return true;
		});
	}
} NoneOf;

struct Tally_impl {
	auto operator()(std::size_t max_val) {
		return Callable([&](auto v) {
			std::vector<std::size_t> result(max_val);
			for (const auto& i : v) {
				result[static_cast<std::size_t>(i)]++;
			}
			return result;
		});
	}
	template <class T, class value_type = typename T::value_type>
	friend auto operator|(const T& v, Tally_impl& c) {
		std::map<value_type, std::size_t> result;
		for (const auto& i : v) {
			result[i]++;
		}
		return result;
	}
} Tally;

struct Reduce_impl {
	template <class T, class F> auto operator()(T memo, F f) {
		return Callable([memo, f](auto v) {
			auto acc = memo;
			for (auto i : v) {
				acc = f(acc, i);
			}
			return acc;
		});
	}
} Reduce;

struct Join_impl {
	auto operator()(std::string separater) {
		return Callable([&](auto v) {
			std::string result;
			bool first = true;
			for (const auto& i : v) {
				if (!std::exchange(first, false)) {
					result += separater;
				}
				result += std::to_string(i);
			}
			return result;
		});
	}
	template <class T> friend auto operator|(const T& v, Join_impl& c) {
		return v | c("");
	}
} Join;

struct At_impl {
	auto operator()(std::size_t l, std::size_t r) {
		return Callable(
		    [l, r](auto v) { return decltype(v)(std::begin(v) + l, std::begin(v) + r); });
	}
} At;
struct Slice_impl {
	auto operator()(std::size_t i, std::size_t cnt) {
		return Callable([i, cnt](auto v) {
			return decltype(v)(std::begin(v) + i, std::begin(v) + i + cnt);
		});
	}
} Slice;

struct Transpose_impl {
	template <class T>
	friend auto operator|(const std::vector<std::vector<T>>& v, Transpose_impl& c) {
		std::size_t h = v.size(), w = v.front().size();
		std::vector result(w, std::vector<T>(h));
		for (std::size_t i = 0; i < h; ++i) {
			assert(v[i].size() == w);
			for (std::size_t j = 0; j < w; ++j) {
				result[j][i] = v[i][j];
			}
		}
		return result;
	}
} Transpose;

template <class T> auto operator*(const std::vector<T>& a, std::size_t n) {
	T result;
	for (std::size_t i = 0; i < n; ++i) {
		result.insert(result.end(), a.begin(), a.end());
	}
	return result;
}
auto operator*(std::string a, std::size_t n) {
	std::string result;
	for (std::size_t i = 0; i < n; ++i) {
		result += a;
	}
	return result;
}

namespace internal {
	template <class T, class U, class = void> struct has_push_back : std::false_type {};
	template <class T, class U>
	struct has_push_back<T, U,
	                     std::void_t<decltype(std::declval<T>().push_back(std::declval<U>()))>>
	    : std::true_type {};
}  // namespace internal
template <
    class Container, class T,
    std::enable_if_t<internal::has_push_back<Container, T>::value, std::nullptr_t> = nullptr>
auto& operator<<(Container& continer, const T& val) {
	continer.push_back(val);
	return continer;
}
template <
    class Container, class T,
    std::enable_if_t<internal::has_push_back<Container, T>::value, std::nullptr_t> = nullptr>
auto operator+(Container continer, const T& val) {
	continer << val;
	return continer;
}

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