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Re: Conversion of a number from string to vector<int>

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On 2011-06-19 17:06:36 -0400, Anonymous said:

> Pete Becker ha scritto:
>> On 2011-06-19 07:13:27 -0400, Anonymous said:
>> Use an unsigned int, and represent the values in base UINT_MAX + 1. 
>> That uses all the bits.
>> 
>> To convert a text string, just use the obvious <g> approach:
>> 
>> set the current value to 0
>> set the current position in the string to the leftmost character
>> while the character at the current position is in '0'..'9'
>> multiply the current value by 10
>> add the value represented by the digit to the current value
>> move the current position one place to the right
>> 
>> Try it with pencil and paper a few times to get the feel of it.
> 
> I don't think the algorithm you are describing can use all the bits 
> available. As I said in my previous thread, the algorithm you are 
> talking about, which is similar to the one I wrote initially, can 
> represent the number in base B, where int B is a power of 10. Since the 
> base it's a power of 10, it cannot profit by all the available bits in 
> the integer.

No, the 10 here is the base of the input. The algorithm I describe is 
simply interpreting a text string that uses base 10 to describe a 
numeric value (extending the algorithm to handle additonal bases is 
left as an exercise). The base B is whatever you use to implement your 
high precision math. Those two bases are independent of each other.

-- 
  Pete
Roundhouse Consulting, Ltd. (www.versatilecoding.com) Author of "The 
Standard C++ Library Extensions: a Tutorial and Reference 
(www.petebecker.com/tr1book)

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Conversion of a number from string to vector<int> Anonymous <anonymous@no.net> - 2011-06-18 19:59 +0200
  Re: Conversion of a number from string to vector<int> "Paul" <pchristor@yahoo.co.uk> - 2011-06-18 20:08 +0100
    Re: Conversion of a number from string to vector<int> Anonymous <anonymous@no.net> - 2011-06-18 23:55 +0200
      Re: Conversion of a number from string to vector<int> Victor Bazarov <v.bazarov@comcast.invalid> - 2011-06-18 18:26 -0400
    Re: Conversion of a number from string to vector<int> Juha Nieminen <nospam@thanks.invalid> - 2011-06-19 06:15 +0000
      Re: Conversion of a number from string to vector<int> "Paul" <pchristor@yahoo.co.uk> - 2011-06-19 08:02 +0100
        Re: Conversion of a number from string to vector<int> Anonymous <anonymous@no.net> - 2011-06-19 12:19 +0200
          Re: Conversion of a number from string to vector<int> "Paul" <pchristor@yahoo.co.uk> - 2011-06-19 16:07 +0100
            Re: Conversion of a number from string to vector<int> Anonymous <anonymous@no.net> - 2011-06-19 17:50 +0200
            Re: Conversion of a number from string to vector<int> Juha Nieminen <nospam@thanks.invalid> - 2011-06-20 06:12 +0000
              Re: Conversion of a number from string to vector<int> "Paul" <pchristor@yahoo.co.uk> - 2011-06-20 09:57 +0100
        Re: Conversion of a number from string to vector<int> Juha Nieminen <nospam@thanks.invalid> - 2011-06-20 06:09 +0000
          Re: Conversion of a number from string to vector<int> "Paul" <pchristor@yahoo.co.uk> - 2011-06-20 09:48 +0100
          Re: Conversion of a number from string to vector<int> Ian Collins <ian-news@hotmail.com> - 2011-06-20 20:59 +1200
            Re: Conversion of a number from string to vector<int> "Paul" <pchristor@yahoo.co.uk> - 2011-06-20 10:17 +0100
              Re: Conversion of a number from string to vector<int> Lasse Reichstein Nielsen <lrn.unread@gmail.com> - 2011-06-20 22:47 +0200
                Re: Conversion of a number from string to vector<int> "Paul" <pchristor@yahoo.co.uk> - 2011-06-20 22:05 +0100
  Re: Conversion of a number from string to vector<int> Ian Collins <ian-news@hotmail.com> - 2011-06-19 08:35 +1200
  Re: Conversion of a number from string to vector<int> Juha Nieminen <nospam@thanks.invalid> - 2011-06-19 06:23 +0000
    Re: Conversion of a number from string to vector<int> Kai-Uwe Bux <jkherciueh@gmx.net> - 2011-06-19 12:14 +0200
    Re: Conversion of a number from string to vector<int> Anonymous <anonymous@no.net> - 2011-06-19 13:13 +0200
      Re: Conversion of a number from string to vector<int> Pete Becker <pete@versatilecoding.com> - 2011-06-19 11:42 -0400
        Re: Conversion of a number from string to vector<int> "Paul" <pchristor@yahoo.co.uk> - 2011-06-19 20:54 +0100
        Re: Conversion of a number from string to vector<int> Anonymous <anonymous@no.net> - 2011-06-19 23:06 +0200
          Re: Conversion of a number from string to vector<int> Pete Becker <pete@versatilecoding.com> - 2011-06-19 17:18 -0400
          Re: Conversion of a number from string to vector<int> "Paul" <pchristor@yahoo.co.uk> - 2011-06-20 00:11 +0100
            Re: Conversion of a number from string to vector<int> "Paul" <pchristor@yahoo.co.uk> - 2011-06-20 00:32 +0100
    Re: Conversion of a number from string to vector<int> Juha Nieminen <nospam@thanks.invalid> - 2011-06-20 06:18 +0000
  Re: Conversion of a number from string to vector<int> Sam <sam@email-scan.com> - 2011-06-21 06:05 -0500

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