CARVIEW |
Select Language
HTTP/1.1 301 Moved Permanently
Server: nginx
Date: Wed, 23 Jul 2025 02:19:27 GMT
Content-Type: text/html; charset=UTF-8
Transfer-Encoding: chunked
Connection: keep-alive
Location: /reference/iostream/cin/
HTTP/1.1 200 OK
Server: nginx
Date: Wed, 23 Jul 2025 02:19:27 GMT
Content-Type: text/html; charset=utf-8
Transfer-Encoding: chunked
Connection: keep-alive
ETag: W/"643d-qGUd6PLNdVzjAdd1uKQ6Y2NF90M"
Content-Encoding: gzip
Object of class istream that represents the standard input stream oriented to narrow characters (of type
The standard input stream is a source of characters determined by the environment. It is generally assumed to be input from an external source, such as the keyboard or a file.
As an object of class istream, characters can be retrieved either as formatted data using the extraction operator (
The object is declared in header
cin is tied to the standard output stream cout (see ios::tie), which indicates that cout's buffer is flushed (see ostream::flush) before each i/o operation performed on cin.
By default, cin is synchronized with stdin (see ios_base::sync_with_stdio).
A program should not mix input operations on cin with input operations on wcin (or with other wide-oriented input operations on stdin): Once an input operation has been performed on either, the standard input stream acquires an orientation (either narrow or wide) that can only be safely changed by calling freopen on stdin.
For more information on the operations supported by cin, see the reference for its type: istream.
Reference
C library:
- <cassert> (assert.h)
- <cctype> (ctype.h)
- <cerrno> (errno.h)
-
<cfenv> (fenv.h)C++11
- <cfloat> (float.h)
-
<cinttypes> (inttypes.h)C++11
- <ciso646> (iso646.h)
- <climits> (limits.h)
- <clocale> (locale.h)
- <cmath> (math.h)
- <csetjmp> (setjmp.h)
- <csignal> (signal.h)
- <cstdarg> (stdarg.h)
-
<cstdbool> (stdbool.h)C++11
- <cstddef> (stddef.h)
-
<cstdint> (stdint.h)C++11
- <cstdio> (stdio.h)
- <cstdlib> (stdlib.h)
- <cstring> (string.h)
-
<ctgmath> (tgmath.h)C++11
- <ctime> (time.h)
-
<cuchar> (uchar.h)C++11
- <cwchar> (wchar.h)
- <cwctype> (wctype.h)
Containers:
-
<array>C++11
- <deque>
-
<forward_list>C++11
- <list>
- <map>
- <queue>
- <set>
- <stack>
-
<unordered_map>C++11
-
<unordered_set>C++11
- <vector>
-
Input/Output:
Multi-threading:
-
<atomic>C++11
-
<condition_variable>C++11
-
<future>C++11
-
<mutex>C++11
-
<thread>C++11
-
Other:
- <algorithm>
- <bitset>
-
<chrono>C++11
-
<codecvt>C++11
- <complex>
- <exception>
- <functional>
-
<initializer_list>C++11
- <iterator>
- <limits>
- <locale>
- <memory>
- <new>
- <numeric>
-
<random>C++11
-
<ratio>C++11
-
<regex>C++11
- <stdexcept>
- <string>
-
<system_error>C++11
-
<tuple>C++11
-
<type_traits>C++11
-
<typeindex>C++11
- <typeinfo>
- <utility>
- <valarray>
- Reference
- <iostream>
- cin
object
<iostream>
std::cin
extern istream cin;
Standard input stream
char
). It corresponds to the C stream stdin.The standard input stream is a source of characters determined by the environment. It is generally assumed to be input from an external source, such as the keyboard or a file.
As an object of class istream, characters can be retrieved either as formatted data using the extraction operator (
operator>>
) or as unformatted data, using member functions such as read.The object is declared in header
<iostream>
with external linkage and static duration: it lasts the entire duration of the program.
In terms of static initialization order, cin is guaranteed to be properly constructed and initialized no later than the first time an object of type ios_base::Init is constructed.
In terms of static initialization order, cin is guaranteed to be properly constructed and initialized no later than the first time an object of type ios_base::Init is constructed, with the inclusion of <iostream> counting as at least one initialization of such objects with static duration.
cin is tied to the standard output stream cout (see ios::tie), which indicates that cout's buffer is flushed (see ostream::flush) before each i/o operation performed on cin.
By default, cin is synchronized with stdin (see ios_base::sync_with_stdio).
A program should not mix input operations on cin with input operations on wcin (or with other wide-oriented input operations on stdin): Once an input operation has been performed on either, the standard input stream acquires an orientation (either narrow or wide) that can only be safely changed by calling freopen on stdin.
For more information on the operations supported by cin, see the reference for its type: istream.
See also
- istream
- Input stream (class)
- cout
- Standard output stream (object)
- wcin
- Standard input stream (wide) (object)
Home page | Privacy policy
© cplusplus.com, 2000-2025 - All rights reserved - v3.3.4s
Spotted an error? contact us
© cplusplus.com, 2000-2025 - All rights reserved - v3.3.4s
Spotted an error? contact us