L-7 MCS 260 Wed 5 Sep 2001

With the logical operators and expressions we can extend the program of the last lecture.

/* L-7 MCS 260 Fri 31 Aug 2001 : rolling a die, extended version */

#include <stdio.>
#include <stdlib.h>          /* for the rand() function */
#include <time.h>            /* time is used as random seed */

int main(void)
{
   int n;                    /* number of times to roll the die */
   int t = 0;                /* target value for the die */
   int i = 0;                /* index counter to control while loop */
   int die = 0;              /* value of the die */

   srand(time(NULL));        /* random seed for random number generator */

   printf("Give number of times to roll the die : ");
   scanf("%d", &n);
   printf("Give target value for the die (between 1 and 6) : ");
   scanf("%d", &t);

   while ((die != t) && (i < n)) /* untill die == t, no more than n rolls */
   {
      die = rand();          /* rand() returns random integer */
      die = die % 6 + 1;     /* die must be in the range 1..6 */
      printf(" %d", die);    /* print space and the die on screen */
      i++;                   /* increment counter */ 
   }
   printf("\n");             /* finish off with new line */

   printf("Got %d after %d times.\n", die, i);

   return 0;
}

/* L-7 MCS 260 Wed 5 Sep 2001 : test on logical operators and expressions */

#include<stdio.h>

int main(void)
{
   int n;      /* some integer number */
   int test;   /* outcome of test */ 


   printf("Give integer : "); scanf("%d", &n);

   printf("Executing one test : \n");

   test = (n > 0);

   printf("  Is n positive? (1=yes,0=no) : %d\n", test);
   printf("  Negation of last statement  : %d\n", !test);

   printf("Combining tests : \n");

   test = (n > 0) && (n % 2 == 1);

   printf("  Is n odd and positive? (1=yes,0=no) : %d\n", test);
   printf("  Negate this is n even or n <= 0     : %d\n", !test);

   test = (n % 2 == 0);
   printf("  Is n even? (1=yes,0=no)     : %d\n", test);
   test = (n <= 0);
   printf("  Is n negative? (1=yes,0=no) : %d\n", test);

   test = (n <= 0) || (n % 2 == 0);

   printf("  Negation of \"n even or n <= 0\"      : %d\n", !test);

   return 0;
}