wcstoimax() and wcstoumax() function in C/C++

The wcstoimax() and wcstoumax() function in C/C++ operate in the same way as the strtoimax() and strtoumax() functions in C++, other than they are used to convert the data of a wide string (wstring) to an integral number of the given base. This function is defined in the header file cinttypes.

Header file:

wcstoimax() method:

wcstoimax() is an abbreviation for "Wide Character String to Maximum Integer". It transforms a wide-character string to a numerical maximum-width signed integer of type intmax_t. It can convert various bases (e.g., decimal, hexadecimal, octal) according to the format of the input text.

Syntax:

It has the following syntax:

#include <inttypes.h>
intmax_t wcstoimax(const wchar_t *npt, wchar_t **endpt, int bases);

Parameters:

npt: The number to be translated into a wide-character string.

endpt: A pointer to wide characters containing the address that represents the function's first incorrect character in the given input string.

bases: The number system's base (for example, 10 for decimal, 16 for hexadecimal, and so on).

Return Value:

The function returns two values, which are as follows:

If there is a proper conversion, the function returns the resultant integral number as an integer value.
If no proper conversion can be done, a value of zero (0) is returned.

Example:

// Program to implement the 
// wstoimax() function in C++
#include <bits/stdc++.h> 
using namespace std; 

// Driver code 
int main() 
{ 
	wstring st = L"Programming"; 

	intmax_t value = wcstoimax(st.c_str(), nullptr, 36); 

	wcout << st << " in base 36 is " << value << " in base 10\n\n"; 

	wchar_t* endp; 

	value = wcstoimax(st.c_str(), &endp, 30); 

	// Because 'w' is not in base 30, string 
	// above this cannot be transformed.
	wcout << "The given input String is = " << st << endl; 

	wcout << "The Number with the base 30 in the given string " << value << " in base 10" << endl; 
   //statement for the display of the next string
	wcout << "the end of the string points to " << endp << endl; 

	return 0; 
} 

Output:

Programming in base 36 is 94215099711813100 in base 10

The given input String is = Programming
The Number with the base 30 in the given string 15309807264430906 in base 10
the end of the string points to

wcstoumax() method:

The wcstoumax() method transforms the wide-character string npt to the integer type uintmax_t. Base input values are 0 and in the range of 2-36. The wcstoumax() function is the same as the wcstoul() and wcstoull() functions. The only distinction is that the returned value corresponds to the type uintmax_t.

Syntax:

It has the following syntax:

#include <inttypes.h>
uintmax_t wcstoumax(const wchar_t *npt, wchar_t **endpt, int bases);

Parameters:

npt: The number to be translated into a wide-character string.

endpt: It is a pointer that contains wide characters containing the address that represents the function's first incorrect character in the given input string.

bases: The number system's base (for example, 10 for decimal, 16 for hexadecimal, and so on).

Example:

// Program to implement the
// wcstoumax() function in C++
#include <bits/stdc++.h> 
using namespace std; 

// Driver code 
int main() 
{ 
	int baseValue = 10; 

	// L is the literal value to represent the wide string
	wstring st = L"123abc"; 
	wchar_t* endp; 
	uintmax_t number; 

	number = wcstoumax(st.c_str(), &endp, baseValue); 

	wcout << "The given input String = " << st << endl; 

	wcout << "The Value stored in the number is: " << number<< endl; 

	if (*endp) { 
		wcout << "The end of the string points to " << endp << endl 
			<< endl; 
	} 
	else { 
		wcout << "Null pointer" << endl 
			<< endl; 
	} 

	//Because there is no number character in this case, the method returns 0. 
	baseValue = 10; 

	wstring st2 = L"abcdeed"; 
	number = wcstoumax(st2.c_str(), &endp, baseValue); 


	wcout << "The given input String = " << st2 << endl; 

	wcout << "The Value stored in the number is: " << number<< endl; 

	if (*endp) { 
		wcout << "The end of the string points to " << endp << endl 
			<< endl; 
	} 
	else { 
		wcout << "Null pointer" << endl 
			<< endl; 
	} 
	return 0; 
} 

Output:

The given input String = 123abc
The Value stored in the number is: 123
The end of the string points to abc

The given input String = abcdeed
The Value stored in the number is: 0
The end of the string points to abcdeed

Uses of wcstoimax() and wcstoumax() function:

When dealing with maximum-width signed integers in multiple bases, use wcstoimax() to convert wide-character sequences representing numbers to intmax_t type.
When dealing with maximum-width unsigned integers in multiple bases, use wcstoumax() to convert wide-character strings denoting integers to uintmax_t type.

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