/*  TruthValues.c  (c) Kari Laitinen

    http://www.naturalprogramming.com

    2013-11-21  File created.
    2013-11-21  Last modification.

    Notes: Old C compilers do not know the stdbool.h file, and
           they do not accept variable declarations between
           action statements inside a function.
*/

#include  <stdio.h>
#include  <stdbool.h> /* Definitions for bool, true, and false */

int main()
{
   bool  true_boolean_variable   =  true ;
   bool  false_boolean_variable  =  false ;

   printf( "\n In C, expressions are evaluated so that\n"
           "\n   - a true  expression has value %d"
           "\n   - a false expression has value %d",
          ( 99 ==  99 ),
          ( 99 ==  88 ) ) ;

   printf( "\n\n Boolean variables can have values"
           "\n   - %d means true "
           "\n   - %d means false\n",
           true_boolean_variable, false_boolean_variable ) ;

   int left_integer  =  4, right_integer ;

   printf( "\n  left  right   <      >=     !=  \n" ) ;

   for ( right_integer  =  0 ;
         right_integer  <  7 ;
         right_integer  ++ )
   {
      printf( "\n   %d     %d", left_integer, right_integer ) ;

      bool  first_truth_value  =  ( left_integer  <  right_integer ) ;
      bool  second_truth_value =  ( left_integer  >= right_integer ) ;
      bool  third_truth_value  =  ( left_integer  != right_integer ) ;

      printf( "      %d      %d      %d", first_truth_value,
              second_truth_value, third_truth_value  ) ;

   }
}