Rewrite the string operation functions-strspns and strcspns in string. h.

Function prototype: size_t strspn (const char * string, const char * strcharset)
Return Value Description: returns an integer that specifies the number of characters in the strcharset string. If 0 is returned, the specified character is not found in the string.
Parameter description:
String: String ending with '/0.
Strcharset: the specified string, ending with '/0.
Function Description:
It is used to calculate the number of specified characters (strcharset) in the characters starting with a string.
Example:

Char strings [] = "1234 ";
Char strcharset [] =: 01234567 ";
Int Len = strspn (string, strcharset); // The LEN value is 4;
Char string2 [] = "8123 ";
Int len2 = strspns (string, strcharset); // The value of len2 is 0.
Char string3 [] = "128676 ";
Int len3 = strspns (string, strcharset); // The value of len3 is 2.

Function implementation:

Size_t strspn (const char * string, const char * strcharset)
{
Assert (null! = String) & (null! = Strcharset ));
Const char * P;
Const char * s;
Size_t COUNT = 0;
For (P = string; * P! = ''; P ++)
{
For (S = strcharset; s! = '/0'; s ++)
{
If (* P = * s)
Break;
}
If (* A = '/0 ')
Return count; // exit if the specified string cannot be found.
Count ++; // otherwise, add count to 1 and continue execution.
}

Return count;
}

Function prototype: size_t strcspn (const char * string, const char * substrset)
Return Value Description: returns an integer that specifies the number of characters starting with a string that are not in the specified string. If the first character of string is in the string substrset, 0 is returned.
Parameter description, which is the same as strspns.
Function Description:
Strcspns are the opposite of strspns. It calculates the number of characters starting with a string that are not in the specified string (that is, substrset. In strcspns, c Represents complement (Supplement ).
Example:

Const char * STR = "hello ";
Const char * substrset = "Lo ";
Int Len = strcspn (STR, substrset); // The LEN value is 2.
Const char * strset2 = "H ";
Int len2 = strcspn (STR, strset2); // The LEN value is 0.
Const char * strset3 = ""; // if the specified string is an empty string, only the terminator'

Function implementation:
Size_t strcspn (const char * STR, const char * strset)
{
Assert (null! = Str) & (null! = Strset ));
Const char * left_str;
Const char * right_str;
Size_t COUNT = 0;
For (left_str = STR; * left_str! = '/0'; left_str ++)
{
For (right_str = strset; * right_str! = '/0'; right_str ++)
{
If (* left_str = * right_str)
{
Break;
} // Exit if the same character is found
}
If (* left_str = * right_str)
{
Return count;
} // If the same character exists, the search ends and the result is returned.
Count ++;
}
Return count;
}