C Articles - Page 41 of 111

In C language both scanf() and gets() functions are defined to get input from external source and pass to system as input. Now there is some characteristics difference between both the functions.Following are the important differences between scanf() and gets() in C −Sr. No.Keyscanf() functiongets() function1DefinitionThe scanf() function can read input from keyboard and stores them according to the given format specifier. It reads the input till encountering a whitespace, newline or EOF.On other hand gets() function is used to receive input from the keyboard till it encounters a newline or EOF. The whitespace is considered as a part of ... Read More

Write a program that compiler and runs both in c and c++ and produces different results.There are multiple types of programs that give different results when compiled in c and c++.i. Using character literals− c and c++ both treat characters differently. In C, they are treated as integer literals whereas, in C++, they are treated as characters.Example Live Demo#include int main(){    printf("%d", sizeof('a'));    return 0; }OutputC : 4 C++: 1ii. Use of binary number − binary values are not considered as binary in c, instead treat it as integer. But in c++, they are treated as binary.Example Live Demo#include int ... Read More

In competitive programming, the most important thing is an effective code. Optimized and faster code is important and can make a difference in the ranks of the programmer.To write an effective c/c++ code in competitive programming, here are some effective tools for writing c/c++ code efficiently, First, let’s recall some basic terms, Template is writing code that does not depend on a particular type.Macro is a named code fragment.Vectors are like automatically resizable dynamic arrays that update size with insertion and deletion of the element.Now, let’s see some basic updates in code that can make in increasing efficiency of code, ... Read More

A program that can interact with the operating system irrespective of the OS on which it runs.Most of the compilers of c/c++ have the power to define macros that detect OS.Some Macros of GCC compiler are −_WIN32: macros for 32 bit and 64-bit Windows OS._WIN64: macros for 64-bit Windows OS._UNIX: macros for UNIX OS._APPLE_: macros for macOS.Based on these macros defined, let’s create a program that will work irrespective of the OS −Example Live Demo#include using namespace std; int main() {    #ifdef _WIN32     system("dir");    #else     system("ls");    #endif     ... Read More

In this article we will be discussing the working, syntax and examples of std::mbrtowc() function in C++ STL.What is std::mbrtowc()?std::mbrtowc() function is an inbuilt function in C++ STL, which is defined in the header file. mbrtowc() means that it converts the narrow multibyte character string to wide character. This function is used to convert a narrow multibyte character to wide character representation.Syntaxsize_t mbrtowc( wchar_t* pwc, char* str, size_t n, mbstate_t* ps);ParametersThe function accepts following parameter(s) −pwc − This is the pointer to the location we want the output to be stored.str − Character string which is used as the ... Read More

In this article we will be discussing the working, syntax and examples of putwchar() function in C++ STL.What is putwchar()?putwchar() function is an inbuilt function in C++ STL, which is defined in the header file. putwchar() function is used to write the wide character on the standard output device. This function takes the wide character from the arguments and writes it on the stdout or standard output of the system.This function is a wide character version of putchar() which is defined in the header file.Syntaxputwchar( wchar_t widec );ParametersThe function accepts following parameter(s) −widec − The wide character which ... Read More

In this article we will be discussing the working, syntax and examples of std::mbrtoc32() function in C++ STL.What is std::mbrtoc32()?std::mbrtoc32() function is an inbuilt function in C++ STL, which is defined in header file. This function is used to convert a narrow multibyte character to UTF-32-character representation.If the associated character pointer is not null, and all other parameters are also accepted then it will convert the corresponding 32-bit character.Syntaxsize_t mbrtoc32( char32_t* pc32, char* str, size_t n, mbstate_t* ps);ParametersThe function accepts following parameter(s) −pc32 − This is the pointer to the location we want the output to be stored.str − ... Read More

In this article we will be discussing the working, syntax and examples of std::mbsrtowcs() function in C++ STL.What is std::mbsrtowcs()?std::mbsrtowcs() function is an inbuilt function in C++ STL, which is defined in the header file. mbsrtowcs() means that it converts the null terminated multibyte character string whose first byte is *src to its wide character representation. This function returns the value according to the conversion.Syntaxsize_t mbsrtowcs( wchar_t* pwc, char** str, size_t n, mbstate_t* ps);ParametersThe function accepts following parameter(s) −pwc − This is the pointer to the location we want the output to be stored.str − Character string which is ... Read More

In this tutorial, we will be discussing a program to understand how to read the alternate nth byte and write it in another file.For this, we will be provided with two .txt files. Our task is to write the contents from one file to another file using Iseek() which is used to change the pointer of the file descriptor.Example#include #include #include #include void func(char arr[], int n){    int f_write = open("start.txt", O_RDONLY);    int f_read = open("end.txt", O_WRONLY);    int count = 0;    while (read(f_write, arr, 1)){       if (count < n) ... Read More

In this tutorial, we will be discussing a program to understand integer literal in C/C++ (Prefixes and suffixes).Integer literals are literals for integer values directly represented in the source code. Further, they are of two types −Prefixes − Prefixes denotes the base of the value. For example, 0x10 indicates hexadecimal value with 0x.Suffixes − Suffixes denotes the type of the value. For example, 8465484156155LL denotes a long long integer.Example Live Demo#include using namespace std; int main(){    //prefixes    cout