Found 35164 Articles for Programming

How to check if a C/C++ string is an int?

Ankith Reddy
Updated on 31-Oct-2023 03:32:51

22K+ Views

There are several methods to check that string is an int or not and one of those method is to use isdigit() to check the string.Here is an example to check whether a string is an int or not in C++ language,Example Live Demo#include #include using namespace std; int main() {    char str[] = "3257fg";    for (int i = 0; i < strlen(str); i++) {       if(isdigit(str[i]))       cout

Left Shift and Right Shift Operators in C/C++

George John
Updated on 25-Jun-2020 10:00:10

2K+ Views

Left ShiftIn the left shift operator, the left operands value is moved left by the number of bits specified by the right operand.Here is an example of left shift operator in C language,Example Live Demo#include int main() {    int y = 28; // 11100    int i = 0;    for(i;i

What does '?' do in C/C++?

Arjun Thakur
Updated on 25-Jun-2020 10:03:05

1K+ Views

The operator ‘?’ is known as ternary operator as it requires three operands to act upon. It can be represented by “ ? : ”. It is also known as conditional operator. The operator improves the performance and reduces the lines of code.Here is the syntax of ternary operator in C language, Expression1 ? Expression2 : Expression3Here is an example of Ternary Operator in C language, Example Live Demo#include int main() {    int a = -1;    double b = 26.4231;    int c = a? printf("True value : %lf", b):printf("False value : 0");    return 0; }OutputHere ... Read More

Purpose of Unions in C/ C++

Ankith Reddy
Updated on 25-Jun-2020 10:04:03

4K+ Views

Union is a user-defined datatype. All the members of union share same memory location. Size of union is decided by the size of largest member of union. If you want to use same memory location for two or more members, union is the best for that.Unions are similar to structures. Union variables are created in same manner as structure variables. The keyword “union” is used to define unions in C language.Here is the syntax of unions in C language, union union_name {    member definition; } union_variables;Here, union_name  − Any name given to the union.member definition  − Set of member ... Read More

C++11 features in Visual Studio 2015

George John
Updated on 30-Jul-2019 22:30:23

220 Views

C++11 is a version of standard C++ language. It was approved by International Organization for Standardization (ISO) on 12 August 2011 then C++14 and C++17. C++11 makes several additions to the core language. Visual C++ implements the vast majority of features in C++11. Some of the following C++11 features in Visual Studio 2015 − nullptr − In the previous nullptr, zero used to be the value and it had a drawback ofimplicit conversion to integral value. The null pointer literal is represented by std::nullptr_t. In this nullptr, no implicit conversion exists. Lambdas − The lambda expression allows to ... Read More

How do malloc() and free() work in C/C++?

Chandu yadav
Updated on 25-Jun-2020 10:05:44

2K+ Views

malloc()The function malloc() is used to allocate the requested size of bytes and it returns a pointer to the first byte of allocated memory. It returns null pointer, if it fails.Here is the syntax of malloc() in C language, pointer_name = (cast-type*) malloc(size);Here, pointer_name  − Any name given to the pointer.cast-type  − The datatype in which you want to cast the allocated memory by malloc().size  − Size of allocated memory in bytes.Here is an example of malloc() in C language, Example Live Demo#include #include int main() {    int n = 4, i, *p, s = 0;   ... Read More

What is the difference between new/delete and malloc/ free in C/ C++?

Arjun Thakur
Updated on 25-Jun-2020 10:07:58

1K+ Views

new/ deleteThe new operator requests for the memory allocation in heap. If the sufficient memory is available, it initializes the memory to the pointer variable and returns its address.The delete operator is used to deallocate the memory. User has the privilege to deallocate the created pointer variable by this delete operator.Here is an example of new/delete operator in C++ language,Example Live Demo#include using namespace std; int main () {    int *ptr1 = NULL;    ptr1 = new int;    float *ptr2 = new float(299.121);    int *ptr3 = new int[28];    *ptr1 = 28;    cout

What is the type of string literals in C/ C++?

Ankith Reddy
Updated on 25-Jun-2020 10:08:32

188 Views

The string literals are the set of characters which is enclosed in double quotes(“ “). Wide-string literals are prefixed with L always.Types of string literals −Sr.No.String Literals & Description1“ “Unprefixed string literal2L” “Wide-string literal3u8” “UTF-8 encoded string literal4u” “UTF-16 encoded string literal5U” “UTF-32 encoded string literal6R” “Raw string literalHere is an example of string literal in C++ language,Example Live Demo#include #include #include using namespace std; int main() {    wchar_t s[] = L"hello world!";    wcout

Why are global variables bad in C/C++?

George John
Updated on 25-Jun-2020 09:52:17

2K+ Views

Global variables are declared and defined outside any function in the program. They hold their values throughout the lifetime of program. They are accessible throughout the execution of program.Non-const global variables are evil because their value can be changed by any function. Using global variables reduces the modularity and flexibility of the program. It is suggested not to use global variables in the program. Instead of using global variables, use local variables in the program.Use ‘g_’ as prefix of the variable name to avoid the naming collisions and for knowledge that variable is global. There is another way also that ... Read More

What are the new changes introduced in C++11?

Arjun Thakur
Updated on 30-Jul-2019 22:30:23

115 Views

C++11 is a version of standard C++ language. It was approved by International Organization for Standardization (ISO) on 12 August 2011 then C++14 and C++17. C++11 makes several additions to the core language. There are some of the new changes introduced in C++11 − nullptr − In the previous nullptr, zero used to be the value and it had a drawback of implicit conversion to integral value. The null pointer literal is represented by std::nullptr_t. In this nullptr, no implicit conversion exists. Lambdas − The lambda expression allows to define functions locally. Anonymous functions are known as lambda. We ... Read More

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