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Re: After doing a lot of the problems on codingbat.com

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Lew Pitcher <lew.pitcher@digitalfreehold.ca> writes:

[...]

> there's a lot more you can do with for() than just count loops
> [examples]
>
> - or even perform a binary search through an ordered array
> int *binsearch(int key, int array[], size_t nelement)
> {
>   size_t lowpt = 0,             /* lowest index in search range */
>          midpt,                 /* midpoint index;  where to search */
>          highpt = nelement - 1; /* highest index in search range */
>
>   /* LOOP through search UNTIL match found OR no elements left to search */
>   for (midpt = (lowpt+highpt)/2;                /* start in the middle */
>        array[midpt] != key && highpt > lowpt;   /* not found AND in bounds*/
>        midpt = (lowpt+highpt)/2)                /* compute new midpoint */
>   { /* ============================ **
>     ** array[midpt] was NOT a match **
>     ** ============================ */
>     if (key > array[midpt])
>       lowpt = midpt + 1;        /* narrow search to between here and high */
>     else
>       highpt = midpt - 1;       /* narrow search to beween low and here */
>   }
>
>   /* loop terminates when entry found OR no more array to search */
>
>   return (array[midpt] == key ? array+midpt : NULL);
> }

    int *
    search( int a[], unsigned n, int key ){
        return  n < 1            ?   0
            :   n == 1           ?   *a == key ? a : 0
            :   a[ n/2 ] > key   ?   search( a,     n/2,   key )
            :                        search( a+n/2, n-n/2, key );
    }

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After doing a lot of the problems on codingbat.com chad <cdalten@gmail.com> - 2020-02-25 06:55 -0800
  Re: After doing a lot of the problems on codingbat.com Anton Shepelev <anton.txt@g{oogle}mail.com> - 2020-02-27 20:02 +0300
    Re: After doing a lot of the problems on codingbat.com James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-02-27 11:41 -0800
      Re: After doing a lot of the problems on codingbat.com Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2020-02-27 14:48 -0700
      Re: After doing a lot of the problems on codingbat.com Bart <bc@freeuk.com> - 2020-02-27 23:17 +0000
        Re: After doing a lot of the problems on codingbat.com James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-02-27 16:40 -0800
          Re: After doing a lot of the problems on codingbat.com Bart <bc@freeuk.com> - 2020-02-28 01:08 +0000
            Re: After doing a lot of the problems on codingbat.com Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-02-28 01:37 -0800
            Re: After doing a lot of the problems on codingbat.com James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-02-28 06:21 -0800
              Re: After doing a lot of the problems on codingbat.com Bart <bc@freeuk.com> - 2020-02-28 16:15 +0000
                Re: After doing a lot of the problems on codingbat.com James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-02-28 10:37 -0800
                Re: After doing a lot of the problems on codingbat.com Bart <bc@freeuk.com> - 2020-02-28 19:22 +0000
                Re: After doing a lot of the problems on codingbat.com David Brown <david.brown@hesbynett.no> - 2020-03-01 14:54 +0100
                Re: After doing a lot of the problems on codingbat.com Bart <bc@freeuk.com> - 2020-03-01 15:36 +0000
                Re: After doing a lot of the problems on codingbat.com David Brown <david.brown@hesbynett.no> - 2020-03-01 17:08 +0100
          Re: After doing a lot of the problems on codingbat.com Richard Damon <Richard@Damon-Family.org> - 2020-02-27 21:57 -0500
          Really??? (Was: After doing a lot of the problems on codingbat.com) gazelle@shell.xmission.com (Kenny McCormack) - 2020-02-28 13:06 +0000
            Re: Really??? (Was: After doing a lot of the problems on codingbat.com) chad <cdalten@gmail.com> - 2020-02-28 05:47 -0800
            Re: Really??? (Was: After doing a lot of the problems on codingbat.com) James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-02-28 05:59 -0800
          Re: After doing a lot of the problems on codingbat.com Bart <bc@freeuk.com> - 2020-02-28 14:04 +0000
            Re: After doing a lot of the problems on codingbat.com Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-28 17:50 +0000
              Re: After doing a lot of the problems on codingbat.com Anton Shepelev <anton.txt@g{oogle}mail.com> - 2020-02-28 20:59 +0300
                Re: After doing a lot of the problems on codingbat.com Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-28 22:37 +0000
              Re: After doing a lot of the problems on codingbat.com Bart <bc@freeuk.com> - 2020-02-29 00:17 +0000
                Re: After doing a lot of the problems on codingbat.com Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-29 01:01 +0000
        Re: After doing a lot of the problems on codingbat.com Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-04-02 19:22 -0700
    Re: After doing a lot of the problems on codingbat.com Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2020-02-27 14:52 -0500
      Re: After doing a lot of the problems on codingbat.com Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-27 20:42 +0000
        Re: After doing a lot of the problems on codingbat.com David Brown <david.brown@hesbynett.no> - 2020-02-27 22:59 +0100
      Re: After doing a lot of the problems on codingbat.com Bart <bc@freeuk.com> - 2020-02-27 20:48 +0000
      Re: After doing a lot of the problems on codingbat.com Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-03-27 20:06 -0700
    Re: After doing a lot of the problems on codingbat.com chad <cdalten@gmail.com> - 2020-02-27 15:28 -0800

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