Strcspn function and basic_istream: gcount Function

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• Parameters
• Return value

size_t strcspn ( const char * str1, const char * str2 );

Get span until character in string

ScansStr1For the first occurrence of any of the characters that are partStr2, Returning the number of charactersStr1Read before this first occurrence.

The search criteria des the terminating null-characters, so the function will return the lengthStr1If none of the charactersStr2Are found inStr1.

Parameters

Str1

C string to be scanned.

Str2

C string containing the characters to match.

 

Return value

The length of the initial partStr1 NotContaining any of the characters that are partStr2.
This is the lengthStr1If none of the characters inStr2Are found inStr1.

 1 /* strcspn example */
 2 #include <stdio.h>
 3 #include <string.h>
 4 
 5 int main ()
 6 {
 7   char str[] = "fcba73";
 8   char keys[] = "1234567890";
 9   int i;
10   i = strcspn (str,keys);
11   printf ("The first number in str is at position %d.\n",i+1);
12   return 0;
13 }

Output:

The first number in str is at position 5

Basic_istream: gcount

Returns the number of characters read during the last unformatted input.

 

streamsize gcount( ) const;

Return Value

The extraction count.

Remarks

Useto read unformatted characters.

 1 // basic_istream_gcount.cpp
 2 // compile with: /EHsc
 3 #include <iostream>
 4 using namespace std;
 5 
 6 int main( ) 
 7 {
 8    cout << "Type the letter 'a': ";
 9 
10    ws( cin );
11    char c[10];
12 
13    cin.get( &c[0],9 );
14    cout << c << endl;
15 
16    cout << cin.gcount( ) << endl;
17 }

Type the letter 'a':a1