C++'da herhangi bir giriş ve çıkış işlemini gerçekleştirmek için iostream başlık dosyalarını kullanmamız gerekir. Başlık dosyası olmadan kullanıcıdan girdi alamayız veya herhangi bir çıktıyı yazdıramayız.
Başlık dosyasının sözdizimi:
#include #include 'iostream.h'
iostream başlık dosyasında iki tür akış vardır
1. Giriş Akışı : Kullanıcıdan herhangi bir girdi almak için girdi akışına ait olan cin'i kullanmamız gerekir.
Giriş akışını kullanmak için sözdizimi:
std::cin>>variable_name
Cin yürütüldüğünde, değer girilene kadar imleç belirli bir ifadede durdurulacaktır. Girilen değer bir değişkende saklanacaktır.
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2. Çıkış Akışı : Çıktıyı yazdırmak için cout çıktı akışındaki yerleşik işlevleri kullanırız
cout'un sözdizimi
std::cout<<variable_name < pre> <p>When cout is executed, the value in the variable will be printed.</p> <h3>Different operations in iostream</h3> <p> <strong>1. Cin</strong> </p> <p>Using cin, we can take input from the user and store the value in the variable. We need to use the cin keyword followed by >> and the variable name.</p> <p> <strong>Syntax:</strong> </p> <pre> std::cin>>variable_name </pre> <p>To use cin, we need to use <strong>#include </strong> as cin belongs to this header file, and without this, an error will occur.</p> <p> <strong>Example code for cin:</strong> </p> <pre> //using header file iostream #include using namespace std; int main() { string name; //cin declaration cin >> name; return 0; } </pre> <p> <strong>Output:</strong> </p> <img src="//techcodeview.com/img/c-tutorial/23/what-is-include-iostream-c.webp" alt="What is include iostream in C++"> <p> <strong>Explanation:</strong> </p> <p>In the above code, we used cin to take the input, so to use cin, we included header file. When the input is taken, the string input is stored in the name variable.</p> <p> <strong>2. Cout</strong> </p> <p>To print the output, we need to use the cout keyword, which belongs to the iostream header file. To use cout, we need to use the cout keyword followed by << and variable or the statement to print the output.</p> <p>The syntax for using cout:</p> <pre> std::cout<<variable_name < pre> <p> <strong>Example of using cout:</strong> </p> <pre> //to use the cout statement, we need to use the iostream header file #include using namespace std; int main() { //cout statement is used here to print the statement cout << 'Hi from cout statement'; return 0;} </pre> <p> <strong>Output:</strong> </p> <img src="//techcodeview.com/img/c-tutorial/23/what-is-include-iostream-c-2.webp" alt="What is include iostream in C++"> <p> <strong>Explanation</strong> :</p> <p>In the above code, we used a cout statement to print the statement. To use the cout statement, we need to include iostream.h header file. Once the cout is executed, statement or variable value will be printing the output. To print any statement, we need to use double quotes (' '), and to print a variable value; we need to use just the variable name without double quotes(' ')</p> <p> <strong>3. Cerr</strong> </p> <p>Cerr is used to print errors in C++, which is present in the iostream header file. If we need to print any error message in the code if any condition fails, then cerr is very helpful.</p> <p>The syntax for cerr is:</p> <pre> cerr<<variable_name < pre> <p>Example:</p> <pre> #include using namespace std; int main() { int a; cin>>a; if(a%2==0){ cout<<'the number entered in even number'<<endl; } else{ std::cerr << 'enter proper number' '
'; return 0; < pre> <p> <strong>Output:</strong> </p> <img src="//techcodeview.com/img/c-tutorial/23/what-is-include-iostream-c-3.webp" alt="What is include iostream in C++"> <p> <strong>Explanation:</strong> </p> <p>In the above example, we used cin to take the input and check if the given number is even or not. If the given number is not even, we need to print an error that the given number is not an even number. We use the cerr keyword in the iostream header file to print this error.</p> <p> <strong>4. Clog:</strong> </p> <p>The clog is also used to print error messages, but unlike cerr, clog is buffered, which means the error message is stored in a buffer and then will be printed, but cerr is unbuffered and will not store the error message in the buffer. The clog also belongs to the iostream header file. As the clog is buffered, it will not show the error message immediately. The clog is preferred more than cerr when efficiency is more important.</p> <p>The syntax for clog:</p> <pre> clog<<variable_name; < pre> <p> <strong>Example:</strong> </p> <pre> #include using namespace std; int main() { clog << 'This message is stored in the buffer'; return 0; } </pre> <p> <strong>Output:</strong> </p> <img src="//techcodeview.com/img/c-tutorial/23/what-is-include-iostream-c-4.webp" alt="What is include iostream in C++"> <p> <strong>Explanation:</strong> </p> <p>In the above code, we are printing an error. To print this error, we use cerr, which belongs to the iostream header file. Before printing the error, we store the error in a buffer.</p> <p> <strong>Example</strong> : For all the input and output streams</p> <pre> #include using namespace std; int main() { int a; string b; cin>>a; if(a%2==0){ cout<<'the number entered is even enter a name'<>b; cout< <b; } else{ std::cerr << 'enter even number' '
'; < pre> <p> <strong>Output:</strong> </p> <img src="//techcodeview.com/img/c-tutorial/23/what-is-include-iostream-c-5.webp" alt="What is include iostream in C++"> <p> <strong>Explanation</strong> : In the above code, we used all the input and output streams in the iostream.h header file.</p> <hr></b;></'the></pre></variable_name;></pre></'the></pre></variable_name></pre></variable_name></pre></variable_name> Cin kullanmak için kullanmamız gerekir #katmak cin bu başlık dosyasına ait olduğundan ve bu olmadan bir hata oluşacaktır.
Cin için örnek kod:
//using header file iostream #include using namespace std; int main() { string name; //cin declaration cin >> name; return 0; } Çıktı:
Açıklama:
Yukarıdaki kodda girişi almak için cin kullandık, dolayısıyla cin kullanmak için başlık dosyasını ekledik. Giriş alındığında, dize girişi ad değişkeninde saklanır.
2. Cout
Çıktıyı yazdırmak için iostream başlık dosyasına ait olan cout anahtar sözcüğünü kullanmamız gerekir. Cout'u kullanmak için cout anahtar sözcüğünü, ardından << ve değişkeni veya çıktıyı yazdıracak ifadeyi kullanmamız gerekir.
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cout'u kullanmanın sözdizimi:
std::cout<<variable_name < pre> <p> <strong>Example of using cout:</strong> </p> <pre> //to use the cout statement, we need to use the iostream header file #include using namespace std; int main() { //cout statement is used here to print the statement cout << 'Hi from cout statement'; return 0;} </pre> <p> <strong>Output:</strong> </p> <img src="//techcodeview.com/img/c-tutorial/23/what-is-include-iostream-c-2.webp" alt="What is include iostream in C++"> <p> <strong>Explanation</strong> :</p> <p>In the above code, we used a cout statement to print the statement. To use the cout statement, we need to include iostream.h header file. Once the cout is executed, statement or variable value will be printing the output. To print any statement, we need to use double quotes (' '), and to print a variable value; we need to use just the variable name without double quotes(' ')</p> <p> <strong>3. Cerr</strong> </p> <p>Cerr is used to print errors in C++, which is present in the iostream header file. If we need to print any error message in the code if any condition fails, then cerr is very helpful.</p> <p>The syntax for cerr is:</p> <pre> cerr<<variable_name < pre> <p>Example:</p> <pre> #include using namespace std; int main() { int a; cin>>a; if(a%2==0){ cout<<\'the number entered in even number\'<<endl; } else{ std::cerr << \'enter proper number\' \'
\'; return 0; < pre> <p> <strong>Output:</strong> </p> <img src="//techcodeview.com/img/c-tutorial/23/what-is-include-iostream-c-3.webp" alt="What is include iostream in C++"> <p> <strong>Explanation:</strong> </p> <p>In the above example, we used cin to take the input and check if the given number is even or not. If the given number is not even, we need to print an error that the given number is not an even number. We use the cerr keyword in the iostream header file to print this error.</p> <p> <strong>4. Clog:</strong> </p> <p>The clog is also used to print error messages, but unlike cerr, clog is buffered, which means the error message is stored in a buffer and then will be printed, but cerr is unbuffered and will not store the error message in the buffer. The clog also belongs to the iostream header file. As the clog is buffered, it will not show the error message immediately. The clog is preferred more than cerr when efficiency is more important.</p> <p>The syntax for clog:</p> <pre> clog<<variable_name; < pre> <p> <strong>Example:</strong> </p> <pre> #include using namespace std; int main() { clog << 'This message is stored in the buffer'; return 0; } </pre> <p> <strong>Output:</strong> </p> <img src="//techcodeview.com/img/c-tutorial/23/what-is-include-iostream-c-4.webp" alt="What is include iostream in C++"> <p> <strong>Explanation:</strong> </p> <p>In the above code, we are printing an error. To print this error, we use cerr, which belongs to the iostream header file. Before printing the error, we store the error in a buffer.</p> <p> <strong>Example</strong> : For all the input and output streams</p> <pre> #include using namespace std; int main() { int a; string b; cin>>a; if(a%2==0){ cout<<\'the number entered is even enter a name\'<>b; cout< <b; } else{ std::cerr << \'enter even number\' \'
\'; < pre> <p> <strong>Output:</strong> </p> <img src="//techcodeview.com/img/c-tutorial/23/what-is-include-iostream-c-5.webp" alt="What is include iostream in C++"> <p> <strong>Explanation</strong> : In the above code, we used all the input and output streams in the iostream.h header file.</p> <hr></b;></\'the></pre></variable_name;></pre></\'the></pre></variable_name></pre></variable_name> Çıktı:
Açıklama :
Yukarıdaki kodda, ifadeyi yazdırmak için cout ifadesini kullandık. Cout ifadesini kullanmak için iostream.h başlık dosyasını eklememiz gerekir. Cout yürütüldüğünde, ifade veya değişken değeri çıktıyı yazdıracaktır. Herhangi bir ifadeyi yazdırmak için çift tırnak (' ') kullanmamız ve değişken bir değer yazdırmamız gerekir; çift tırnak olmadan sadece değişken adını kullanmamız gerekiyor(' ')
3. Sertifika
Cerr, iostream başlık dosyasında bulunan C++ hatalarını yazdırmak için kullanılır. Herhangi bir koşulun başarısız olması durumunda kodda herhangi bir hata mesajı yazdırmamız gerekiyorsa, cerr çok faydalıdır.
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Cerr'in sözdizimi şöyledir:
cerr<<variable_name < pre> <p>Example:</p> <pre> #include using namespace std; int main() { int a; cin>>a; if(a%2==0){ cout<<\'the number entered in even number\'<<endl; } else{ std::cerr << \'enter proper number\' \'
\'; return 0; < pre> <p> <strong>Output:</strong> </p> <img src="//techcodeview.com/img/c-tutorial/23/what-is-include-iostream-c-3.webp" alt="What is include iostream in C++"> <p> <strong>Explanation:</strong> </p> <p>In the above example, we used cin to take the input and check if the given number is even or not. If the given number is not even, we need to print an error that the given number is not an even number. We use the cerr keyword in the iostream header file to print this error.</p> <p> <strong>4. Clog:</strong> </p> <p>The clog is also used to print error messages, but unlike cerr, clog is buffered, which means the error message is stored in a buffer and then will be printed, but cerr is unbuffered and will not store the error message in the buffer. The clog also belongs to the iostream header file. As the clog is buffered, it will not show the error message immediately. The clog is preferred more than cerr when efficiency is more important.</p> <p>The syntax for clog:</p> <pre> clog<<variable_name; < pre> <p> <strong>Example:</strong> </p> <pre> #include using namespace std; int main() { clog << 'This message is stored in the buffer'; return 0; } </pre> <p> <strong>Output:</strong> </p> <img src="//techcodeview.com/img/c-tutorial/23/what-is-include-iostream-c-4.webp" alt="What is include iostream in C++"> <p> <strong>Explanation:</strong> </p> <p>In the above code, we are printing an error. To print this error, we use cerr, which belongs to the iostream header file. Before printing the error, we store the error in a buffer.</p> <p> <strong>Example</strong> : For all the input and output streams</p> <pre> #include using namespace std; int main() { int a; string b; cin>>a; if(a%2==0){ cout<<\'the number entered is even enter a name\'<>b; cout< <b; } else{ std::cerr << \'enter even number\' \'
\'; < pre> <p> <strong>Output:</strong> </p> <img src="//techcodeview.com/img/c-tutorial/23/what-is-include-iostream-c-5.webp" alt="What is include iostream in C++"> <p> <strong>Explanation</strong> : In the above code, we used all the input and output streams in the iostream.h header file.</p> <hr></b;></\'the></pre></variable_name;></pre></\'the></pre></variable_name> Çıktı:
Açıklama:
Yukarıdaki kodda bir hata yazdırıyoruz. Bu hatayı yazdırmak için iostream başlık dosyasına ait olan cerr dosyasını kullanıyoruz. Hatayı yazdırmadan önce hatayı bir arabellekte saklarız.
Örnek : Tüm giriş ve çıkış akışları için
#include using namespace std; int main() { int a; string b; cin>>a; if(a%2==0){ cout<<\\'the number entered is even enter a name\\'<>b; cout< <b; } else{ std::cerr << \\'enter even number\\' \\'
\\'; < pre> <p> <strong>Output:</strong> </p> <img src="//techcodeview.com/img/c-tutorial/23/what-is-include-iostream-c-5.webp" alt="What is include iostream in C++"> <p> <strong>Explanation</strong> : In the above code, we used all the input and output streams in the iostream.h header file.</p> <hr></b;></\\'the>