From: Radical DOT NetSurfer AT delorie DOT com
Newsgroups: comp.os.msdos.djgpp
Subject: Error trying to Shift Longs & LongLong
Date: Wed, 23 Apr 2003 13:31:50 -0400
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To: djgpp AT delorie DOT com
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The program below works 100% correctly in Borland,
but produces one very obvious problem when run from
DJGPP.....

    x = (1 << m);

why should shifting by a (-1) create such an unsual value?

Shouldn't shifting by "all" bits give Zero ?

Why is the "sign-bit" apparently being shifted into things?

Long Long appears to be a special contrivance, so we're not
too concerned about their artificial behavior.

Comments welcomed!

Email to: RadSurfer AT yahoo DOT com 

-------------------------------------------------------------------------
/* Program to create Binary Table and Complements
   April 15th, 2003  19:00
*/

#include <stdio.h>

int main(int argc, char **argv) {
int x = 0, n = 0, b = 0, p = 0, c = 0, m = 0;

  //Generate 1 to 2048
  for (m=(-1); m<12; ++m) {
    x = (1 << m);

    printf("% 5d  % 5d  ",(m+1), x);

    for(n=11; n>(-1); --n) {
    b = (1 << n);
    p = (x & b);

   // printf("%d and %d = %d\n", x, b, ( p ? 1 : 0 ) );
      printf("%d", ( p ? 1 : 0 ) ); //Foward Binary
   }
    printf("  ");
    c = 0;
    for(n=11; n>(-1); --n) {
    b = (1 << n);
    p = (x & b);

      printf("%d", ( p ? 0 : 1 ) ); //Inverted Binary

      if ( !p ) c += b;  //Accumulate Non-Zero Values
   }
   printf("  % 5d\n", c);  //Print Complementary Value
   } //x++

return(0);
} //Main