You can utilize the fact that the character encodings for digits are all in order from 48 (for ‘0’) to 57 (for ‘9’). This holds true for ASCII, UTF-x and practically all other encodings (see comments below for more on this). Therefore the integer value for any digit is the digit minus ‘0’ (or 48). … Read more
The difference here is that will place “Hello world” in the read-only parts of the memory, and making s a pointer to that makes any writing operation on this memory illegal. While doing: puts the literal string in read-only memory and copies the string to newly allocated memory on the stack. Thus making legal.
The documentation for strtok_r is quite clear. The strtok_r() function is a reentrant version strtok(). The saveptr argument is a pointer to a char * variable that is used internally by strtok_r() in order to maintain context between successive calls that parse the same string. On the first call to strtok_r(), str should point to the string … Read more
lvalue means “left value” — it should be assignable. You cannot change the value of text since it is an array, not a pointer. Either declare it as char pointer (in this case it’s better to declare it as const char*): Or use strcpy:
The string class has a constructor that takes a NULL-terminated C-string:
Job done 🙂
will print out the char with Unicode code point 1 (start-of-heading char, which isn’t printable; see this table: C0 Controls and Basic Latin, same as ASCII) will print out the char with Unicode code point 49 (one corresponding to ‘1’) If you want to convert a digit (0-9), you can add 48 to it and cast, or something … Read more
The declaration and initialization declares a pointer array and make it point to a constant array of 31 characters. The declaration and initialization declares an array of characters, containing 31 characters. And yes, the size of the arrays is 31, as it includes the terminating ‘\0’ character. Laid out in memory, it will be something like this for the … Read more
Job done 🙂
In C++, there are three distinct character types: char signed char unsigned char If you are using character types for text, use the unqualified char: it is the type of character literals like ‘a’ or ‘0’ (in C++ only, in C their type is int) it is the type that makes up C strings like … Read more