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Range of characters in C++

  1. Jun 28, 2005 #1
    i have a little problem i m not able to check if an input character is in a specified range of characters. i.e is this char between A and Z let s say.
    I tried to use the ascII but it didn t work out; no syntax errors at compile time but the error occurs at run time.
    this is the code i used:
    if(var<=75 && var >=65) //75 is letter K and 65 letter A
    and var is a char *.

    where is my problem?
  2. jcsd
  3. Jun 28, 2005 #2


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    var is a char*? The value of a char* is a pointer, so you're checking if a pointer is less than 75, which doesn't make sense. I can't remember, but you might want to check something like &var or var& or var* or something like that. Again, my memory might be off, but should you have two ampersands? What is the actual error you're getting?
  4. Jun 28, 2005 #3
    First of all, a char* is a 32-bit hex value that points to some region of memory. To get the first value pointed to by var, you can either use *var or var[0].

    If you want to compare single characters, you can use

    Code (Text):
    if (*var <= 'K' || *var >= 'A')
    without problems.
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