#include <compare>
#include <initializer_list>
namespace std {
template<class charT> struct char_traits;
template<> struct char_traits<char>;
template<> struct char_traits<char8_t>;
template<> struct char_traits<char16_t>;
template<> struct char_traits<char32_t>;
template<> struct char_traits<wchar_t>;
template<class charT, class traits = char_traits<charT>, class Allocator = allocator<charT>>
class basic_string;
template<class charT, class traits, class Allocator>
constexpr basic_string<charT, traits, Allocator>
operator+(const basic_string<charT, traits, Allocator>& lhs,
const basic_string<charT, traits, Allocator>& rhs);
template<class charT, class traits, class Allocator>
constexpr basic_string<charT, traits, Allocator>
operator+(basic_string<charT, traits, Allocator>&& lhs,
const basic_string<charT, traits, Allocator>& rhs);
template<class charT, class traits, class Allocator>
constexpr basic_string<charT, traits, Allocator>
operator+(const basic_string<charT, traits, Allocator>& lhs,
basic_string<charT, traits, Allocator>&& rhs);
template<class charT, class traits, class Allocator>
constexpr basic_string<charT, traits, Allocator>
operator+(basic_string<charT, traits, Allocator>&& lhs,
basic_string<charT, traits, Allocator>&& rhs);
template<class charT, class traits, class Allocator>
constexpr basic_string<charT, traits, Allocator>
operator+(const charT* lhs,
const basic_string<charT, traits, Allocator>& rhs);
template<class charT, class traits, class Allocator>
constexpr basic_string<charT, traits, Allocator>
operator+(const charT* lhs,
basic_string<charT, traits, Allocator>&& rhs);
template<class charT, class traits, class Allocator>
constexpr basic_string<charT, traits, Allocator>
operator+(charT lhs,
const basic_string<charT, traits, Allocator>& rhs);
template<class charT, class traits, class Allocator>
constexpr basic_string<charT, traits, Allocator>
operator+(charT lhs,
basic_string<charT, traits, Allocator>&& rhs);
template<class charT, class traits, class Allocator>
constexpr basic_string<charT, traits, Allocator>
operator+(const basic_string<charT, traits, Allocator>& lhs,
const charT* rhs);
template<class charT, class traits, class Allocator>
constexpr basic_string<charT, traits, Allocator>
operator+(basic_string<charT, traits, Allocator>&& lhs,
const charT* rhs);
template<class charT, class traits, class Allocator>
constexpr basic_string<charT, traits, Allocator>
operator+(const basic_string<charT, traits, Allocator>& lhs,
charT rhs);
template<class charT, class traits, class Allocator>
constexpr basic_string<charT, traits, Allocator>
operator+(basic_string<charT, traits, Allocator>&& lhs,
charT rhs);
template<class charT, class traits, class Allocator>
constexpr bool
operator==(const basic_string<charT, traits, Allocator>& lhs,
const basic_string<charT, traits, Allocator>& rhs) noexcept;
template<class charT, class traits, class Allocator>
constexpr bool operator==(const basic_string<charT, traits, Allocator>& lhs,
const charT* rhs);
template<class charT, class traits, class Allocator>
constexpr see below operator<=>(const basic_string<charT, traits, Allocator>& lhs,
const basic_string<charT, traits, Allocator>& rhs) noexcept;
template<class charT, class traits, class Allocator>
constexpr see below operator<=>(const basic_string<charT, traits, Allocator>& lhs,
const charT* rhs);
template<class charT, class traits, class Allocator>
constexpr void
swap(basic_string<charT, traits, Allocator>& lhs,
basic_string<charT, traits, Allocator>& rhs)
noexcept(noexcept(lhs.swap(rhs)));
template<class charT, class traits, class Allocator>
basic_istream<charT, traits>&
operator>>(basic_istream<charT, traits>& is,
basic_string<charT, traits, Allocator>& str);
template<class charT, class traits, class Allocator>
basic_ostream<charT, traits>&
operator<<(basic_ostream<charT, traits>& os,
const basic_string<charT, traits, Allocator>& str);
template<class charT, class traits, class Allocator>
basic_istream<charT, traits>&
getline(basic_istream<charT, traits>& is,
basic_string<charT, traits, Allocator>& str,
charT delim);
template<class charT, class traits, class Allocator>
basic_istream<charT, traits>&
getline(basic_istream<charT, traits>&& is,
basic_string<charT, traits, Allocator>& str,
charT delim);
template<class charT, class traits, class Allocator>
basic_istream<charT, traits>&
getline(basic_istream<charT, traits>& is,
basic_string<charT, traits, Allocator>& str);
template<class charT, class traits, class Allocator>
basic_istream<charT, traits>&
getline(basic_istream<charT, traits>&& is,
basic_string<charT, traits, Allocator>& str);
template<class charT, class traits, class Allocator, class U>
constexpr typename basic_string<charT, traits, Allocator>::size_type
erase(basic_string<charT, traits, Allocator>& c, const U& value);
template<class charT, class traits, class Allocator, class Predicate>
constexpr typename basic_string<charT, traits, Allocator>::size_type
erase_if(basic_string<charT, traits, Allocator>& c, Predicate pred);
using string = basic_string<char>;
using u8string = basic_string<char8_t>;
using u16string = basic_string<char16_t>;
using u32string = basic_string<char32_t>;
using wstring = basic_string<wchar_t>;
int stoi(const string& str, size_t* idx = nullptr, int base = 10);
long stol(const string& str, size_t* idx = nullptr, int base = 10);
unsigned long stoul(const string& str, size_t* idx = nullptr, int base = 10);
long long stoll(const string& str, size_t* idx = nullptr, int base = 10);
unsigned long long stoull(const string& str, size_t* idx = nullptr, int base = 10);
float stof(const string& str, size_t* idx = nullptr);
double stod(const string& str, size_t* idx = nullptr);
long double stold(const string& str, size_t* idx = nullptr);
string to_string(int val);
string to_string(unsigned val);
string to_string(long val);
string to_string(unsigned long val);
string to_string(long long val);
string to_string(unsigned long long val);
string to_string(float val);
string to_string(double val);
string to_string(long double val);
int stoi(const wstring& str, size_t* idx = nullptr, int base = 10);
long stol(const wstring& str, size_t* idx = nullptr, int base = 10);
unsigned long stoul(const wstring& str, size_t* idx = nullptr, int base = 10);
long long stoll(const wstring& str, size_t* idx = nullptr, int base = 10);
unsigned long long stoull(const wstring& str, size_t* idx = nullptr, int base = 10);
float stof(const wstring& str, size_t* idx = nullptr);
double stod(const wstring& str, size_t* idx = nullptr);
long double stold(const wstring& str, size_t* idx = nullptr);
wstring to_wstring(int val);
wstring to_wstring(unsigned val);
wstring to_wstring(long val);
wstring to_wstring(unsigned long val);
wstring to_wstring(long long val);
wstring to_wstring(unsigned long long val);
wstring to_wstring(float val);
wstring to_wstring(double val);
wstring to_wstring(long double val);
namespace pmr {
template<class charT, class traits = char_traits<charT>>
using basic_string = std::basic_string<charT, traits, polymorphic_allocator<charT>>;
using string = basic_string<char>;
using u8string = basic_string<char8_t>;
using u16string = basic_string<char16_t>;
using u32string = basic_string<char32_t>;
using wstring = basic_string<wchar_t>;
}
template<class T> struct hash;
template<class A> struct hash<basic_string<char, char_traits<char>, A>>;
template<class A> struct hash<basic_string<char8_t, char_traits<char8_t>, A>>;
template<class A> struct hash<basic_string<char16_t, char_traits<char16_t>, A>>;
template<class A> struct hash<basic_string<char32_t, char_traits<char32_t>, A>>;
template<class A> struct hash<basic_string<wchar_t, char_traits<wchar_t>, A>>;
inline namespace literals {
inline namespace string_literals {
constexpr string operator""s(const char* str, size_t len);
constexpr u8string operator""s(const char8_t* str, size_t len);
constexpr u16string operator""s(const char16_t* str, size_t len);
constexpr u32string operator""s(const char32_t* str, size_t len);
constexpr wstring operator""s(const wchar_t* str, size_t len);
}
}
}