logb() function in C++ STL

iswalpha() function in C++ STL

Last Updated : 21 Aug, 2018

The iswalpha() is a built-in function in C++ STL which checks if the given wide character is an alphabet or not. It is defined within the cwctype header file of C++. The following characters are alphanumeric:

Uppercase letters: A to Z
Lowercase letters: a to z

Syntax:

int iswalpha(ch)

Parameter: The function accepts a single mandatory parameter ch which specifies the wide character which we have to check that if it is an alphabet or not. Return Value: The function returns two values:

If the ch is an alphanumeric character, then a non-zero value is returned.
If it is not an alphanumeric character, then 0 is returned.

Below programs illustrate the above function. Program 1:

CPP

// Program to illustrate
// iswalpha() function
#include <cwctype>
#include <iostream>
using namespace std;

int main()
{

    wchar_t ch1 = 'Q';
    wchar_t ch2 = 'g';

    iswalpha(ch1) ? wcout << ch1 
    << "is alphabet " : wcout << ch1
    << " is not alphabet ";

    wcout << endl;
    iswalpha(ch2) ? wcout << ch2 
    << " is an alphabet " : wcout << ch2
    << " is not an alphabet ";

    return 0;
}

Output:

Q is an alphabet 
g is an alphabet

Program 2:

CPP

// Program to illustrate
// iswalpha() function
#include <cwctype>
#include <iostream>
using namespace std;

int main()
{

    wchar_t ch1 = 'w';
    wchar_t ch2 = '2';

    iswalpha(ch1) ? wcout << ch1 << 
    " is alphabet " : wcout << ch1 
    << " is not alphabet ";

    wcout << endl;
    iswalpha(ch2) ? wcout << ch2 << 
    " is an alphabet " : wcout << ch2 
    << " is not an alphabet ";

    return 0;
}

Output:

w is an alphabet 
2 is not an alphabet

logb() function in C++ STL

I

IshwarGupta

Improve

Article Tags :

Practice Tags :

Similar Reads

iswalnum() function in C++ STL

The iswalnum() is a built-in function in C++ STL which checks if the given wide character is an alphanumeric character or not. It is defined within the cwctype header file of C++. The following characters are alphanumeric: Uppercase letters: A to Z Lowercase letters: a to z Digits: 0 to 9 Syntax: in

scalbln() function in C++ STL

The scalbln() is a built-in function in C++ STL which takes two arguments and scales x by FLT_RADIX raised to the power n. The function returns the product of x and FLT_RADIX raised to the power n. FLT_RADIX: It is the value of the radix (integer base) of the exponent representation. Syntax: scalbln

strtol() function in C++ STL

The strtol() function is a builtin function in C++ STL which converts the contents of a string as an integral number of the specified base and return its value as a long int. Syntax: strtol(s, &end, b) Parameters: The function accepts three mandatory parameters which are described as below: s: s

logb() function in C++ STL

The logb() is a builtin function in C++ STL which returns the logarithm of |x|, using FLT_RADIX as base for the logarithm. In general, the value of FLT_RADIX is 2, so logb() is equivalent to log2()(for positive values only). Syntax: logb(val) Parameter: The function accepts a single mandatory parame

list end() function in C++ STL

The list::end() is a built-in function in C++ STL which is used to get an iterator to past the last element. By past the last element it is meant that the iterator returned by the end() function return an iterator to an element which follows the last element in the list container. It can not be used

map find() function in C++ STL

The std::map::find() is a built-in function in C++ STL that is used to find an element with given key in the map. It is a member function of std::map container so we can directly use it with any map.Syntaxmap_name.find(key)Parameterskey: Key of the pair to be searched in the map container.Return Val

map rend() function in C++ STL

The rend() function is an inbuilt function in C++ STL which returns a reverse iterator pointing to the theoretical element right before the first key-value pair in the map(which is considered its reverse end). Syntax: map_name.rend() Parameters:The function does not take any parameter. Return Value:

strol() function in C++

The strtol() function in C++ interprets the contents of a string as an integral number of the specified base and return its value as a long int.This function also sets an end pointer that points to the first character after the last valid numeric character of the string, if there is no such characte

iswcntrl() function in C/C++

The iswcntrl() is a built-in function in C++ STL which checks if the given wide character is a control character or not. It is defined within the cwctype header file of C/C++. Syntax: int iswcntrl(wint_t ch) Parameter: The function accepts a single mandatory parameter ch which specifies the wide cha

iswblank() function in C/C++

The iswblank() is a built-in function in C/C++ which checks if the given wide character is a blank character or not. It is defined within the cwctype header file of C++. Syntax: int iswblank(ch) Parameter: The function accepts a single mandatory parameter ch which specifies the wide character which