Operations on characters

Even though characters are integer values, there are only a few meaningful things we want to do with or to them. The first two things are declaration and assignment. Let's declare some character variables with the following code:

  signed char  aChar;
         char  c1 , c2, c3 , c4;
  unsigned char  aByte;

In C, char is the intrinsic data type that is one byte (8 bits). aChar is a variable that holds a signed value between -128 and 127 (inclusive). We explicitly use the signed keyword, even though it is unnecessary. Next, we declare four single-byte variables, each also having the -128 to 127range. Variables are assumed to besignedunless explicitly specified asunsigned. Finally, we declare an unsigned single-byte variable,aByte, which can hold a value between 0 to 128.

We can also assign values at the declaration, as follows:

  signed char aChar = 'A';
         char    c1 = 65 ; 
         char    c2 = 'a...