C and C++ reference

C++ reference C++11, C++14, C++17, C++20, C++23, C++26  │  Compiler support C++11, C++14, C++17, C++20, C++23, C++26
Language Preprocessor − Comments ASCII chart Basic concepts     Keywords     Names (lookup)     Types (fundamental types)     The main function     Modules (C++20)     Contracts (C++26) Expressions     Value categories     Evaluation order     Operators (precedence)     Conversions − Literals     Constant expressions Statements     if − switch     for − range-for (C++11)     while − do-while Declarations − Initialization Functions − Overloading Coroutines (C++20) Classes (unions) Templates − Exceptions Freestanding implementations Standard library (headers) Named requirements Language support library Program utilities     Signals − Non-local jumps Basic memory management Variadic functions source_location (C++20) Comparison utilities (C++20) Type support − type_info numeric_limits − exception initializer_list (C++11) Coroutine support (C++20) Contract support (C++26) Concepts library (C++20)	Diagnostics library Assertions − System error (C++11) Exception types − Error numbers basic_stacktrace (C++23) Debugging support (C++26) Memory management library Allocators − Smart pointers Memory resources (C++17) Metaprogramming library (C++11) Type traits − ratio integer_sequence (C++14) General utilities library Function objects − hash (C++11) Swap − Type operations (C++11) Integer comparison (C++20) pair − tuple (C++11) optional (C++17) expected (C++23) variant (C++17) − any (C++17) bitset − Bit manipulation (C++20) Containers library vector − deque − array (C++11) list − forward_list (C++11) inplace_vector (C++26) hive (C++26) map − multimap − set − multiset unordered_map (C++11) unordered_multimap (C++11) unordered_set (C++11) unordered_multiset (C++11) Container adaptors span (C++20) − mdspan (C++23) Iterators library Ranges library (C++20) Range factories − Range adaptors generator (C++23) Algorithms library Numeric algorithms Execution policies (C++17) Constrained algorithms (C++20)	Strings library basic_string − char_traits basic_string_view (C++17) Text processing library Primitive numeric conversions (C++17) Formatting (C++20) − Localization text_encoding (C++26) Regular expressions (C++11)     basic_regex − Algorithms     Default regular expression grammar Null-terminated sequence utilities:     byte − multibyte − wide Numerics library Common math functions Mathematical special functions (C++17) Mathematical constants (C++20) Basic linear algebra algorithms (C++26) Data-parallel types (SIMD) (C++26) Pseudo-random number generation Floating-point environment (C++11) complex − valarray Date and time library Calendar (C++20) − Time zone (C++20) Input/output library Print functions (C++23) Stream-based I/O − I/O manipulators basic_istream − basic_ostream Synchronized output (C++20) File systems (C++17) Concurrency support library (C++11) thread − jthread (C++20) atomic − atomic_flag atomic_ref (C++20) − memory_order Mutual exclusion − Condition variables Futures − Semaphores (C++20) latch (C++20) − barrier (C++20) Safe Reclamation (C++26) Execution support library (C++26) Feature test macros (C++20) Language − Standard library − Headers
Technical specifications     Standard library extensions  (library fundamentals TS)     resource_adaptor − invocation_type     Standard library extensions v2  (library fundamentals TS v2)     propagate_const − ostream_joiner − randint     observer_ptr − Detection idiom     Standard library extensions v3  (library fundamentals TS v3)     scope_exit − scope_fail − scope_success − unique_resource		Parallelism library extensions v2 (parallelism TS v2) simd Concurrency library extensions (concurrency TS) Transactional Memory  (TM TS) Reflection  (reflection TS)
External Links  −  Non-ANSI/ISO Libraries  −  Index  −  std Symbol Index
C reference C89, C95, C99, C11, C17, C23  │  Compiler support C99, C23
Language Basic concepts Keywords Preprocessor Expressions Declaration Initialization Functions Statements Headers Type support	Program utilities Variadic functions Diagnostics library Dynamic memory management Strings library Null-terminated strings:    byte  −   multibyte  −   wide Date and time library Localization library Input/output library	Algorithms library Numerics library Common mathematical functions Floating-point environment (C99) Pseudo-random number generation Complex number arithmetic (C99) Type-generic math (C99) Bit manipulation (C23) Checked integer arithmetic (C23) Concurrency support library (C11)
Technical specifications    Dynamic memory extensions  (dynamic memory TR)    Floating-point extensions, Part 1  (FP Ext 1 TS)    Floating-point extensions, Part 4  (FP Ext 4 TS)
External Links  −  Non-ANSI/ISO Libraries  −  Index  −  Symbol Index

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27 August 2025: Sorry for the delay, everyone. Finding the time to work on the upgrade has proven more challenging than expected. Hopefully we'll be able to get back to normal in the near future. 30 March 2025: The site will be in a temporary read-only mode in the next few weeks to facilitate some long-overdue software updates. Hopefully it won't take too long, but we all know how database migrations can sometimes turn evil. Please send any concerns/ideas/moral-support to comments@cppreference.com. 7 June 2019: New version of the offline archive