Thread: range of characters

howdy,

the following code will select a random char however the ASCII values 91 thru 96 are not letters. how would i ignore ASCII values 91 thru 97.

Code:

#include <stdio.h>
#include <iostream.h>
#include <stdlib.h>
#include <time.h>

 
int main ()
{
  system("clear");
  cout<<"~~~~~~~~~~~~~~~~~~~~~~~~~~"<<endl;
  int c;
  int i;
  int count= 0;
  int under = 0;
  int over = 0;
  srand(time(0));
  
    for( c = 0; c < 20; c++){
      int i = (rand()%57)+65;
      char letter  = (i) ;//get ASCII code
      cout<<"Letter: "<<letter<<" ASCII code: "<<i<<endl;
      if(i > 90 && i < 97){
	cout<<"  ------#"<<endl;      
	count++;}
      if(i < 90){
	under++;}
      if(i >97){
	over++;}
    }
  cout<<"\nfail numbers: "<<count<<endl;
  cout<<"Under: "<<under<<endl;
  cout<<"Over: "<<over<<endl;
  return 0;
}

Thanks

M.R.

What do you mean by ignore?

Code:

    for( c = 0; c < 20; c++){
      int i = (rand()%57)+65;
      if(i > 90 && i < 97){
         cout<<"  ------#"<<endl;      
         count++;
         if(i < 90){
            under++;}
         if(i >97){
            over++;}
      }
      else{
          char letter  = (i) ;//get ASCII code
          cout<<"Letter: "<<letter<<" ASCII code: "<<i<<endl;
      }
    }

howdy,

What do you mean by ignore?

what i want to do is exclude the values 91 - 96 from the random number selection allowing the values 65 - 90 ASCII upper case characters and values 97-122 ASCII lower case characters.

i hope this makes my question a bit clearer.

BTW i havent tryed seoopy's code but it looks like it may work

M.R.

Hi itld,
Since the range that you wish to exclude is continious its prety easy. here is a little maths about the task
R[65..122] -> |R| = 122-65 = 57
but X%Y gives a number between [0..y-1] so the value is 58
R[65..122]^[91..96] ->58-6

Code:

  for(c = 0; c < 20000 ; c++){
    int i = (rand()%(58-6))+65;
    if (i>90)
      i+=6;
    char letter  = (i) ;//get ASCII code
    cout<<"Letter: "<<letter<<" ASCII code: "<<i<<endl;
  }

that fragmet will give you values between 'A'..'Z' and 'a','z'

damyan

howdy damyan,
when i saw you name i thought i had been mysteriously tranported over to loobians house.
again you hit it right on the head.
i just got the one about header files ill study it and post back latter.

thanks
M.R.