int main() {
char m[4][100];
char r[100];
for (int i = 0; i < 4; i++)
scanf("%s", m[i]);
int f = get_nth(m, 0);
int l = get_nth(m, strlen(m[0])-1);
for (int i = 1; i < strlen(m[i])-1; i++) {
r[i-1] = ((f*get_nth(m,i)) + l) % 257;
}
r[strlen(m[0])-1] = '\0';
printf("%s\n", r);
}
static char *
discover_traversible(dpl_addrlist_t *addrlist)
{
int n;
int i;
int j;
char *s;
dpl_status_t r;
char *addr;
#define MAXADDRS 32
int naddrs = 0;
char *addrs[MAXADDRS];
n = dpl_addrlist_count(addrlist);
for (i = 0 ; i < n ; i++)
{
addr = get_nth(addrlist, i);
for (j = 0 ; j < naddrs ; j++)
{
if (!strcmp(addr, addrs[j]))
break;
}
if (j == naddrs)
{
dpl_assert_int_ne(naddrs, MAXADDRS);
addrs[naddrs++] = addr;
}
else
free(addr);
}
/* sort the results into a predictable order */
qsort(addrs, naddrs, sizeof(char*), compare_addrs);
/* concatenate the strings into one big one */
n = 0;
for (i = 0 ; i < naddrs ; i++)
n += strlen(addrs[i])+1;
s = malloc(n);
dpl_assert_ptr_not_null(s);
s[0] = '\0';
for (i = 0 ; i < naddrs ; i++)
{
if (i)
strcat(s, ",");
strcat(s, addrs[i]);
free(addrs[i]);
}
return s;
}
int get_nth(BTREE *bt, long page, int n, KEY *key, ITEM *u)
{
PAGE_ADDRESS *p;
int i, cont;
if (page == BTREE_NULL)
{
btree_errno = INTERN_MIST;
return -1;
}
p = (PAGE_ADDRESS *) get_page(bt, page);
if (p->child0 >= n)
return get_nth(bt, p->next0, n, key, u);
n -= p->child0;
i = 0;
while (i < p->nkeys-1)
{
if (1 == n)
{
l1:
memcpy(key, nth_key(bt, p, i), bt->realkeysize);
*u = p->s[i];
return 0;
}
n--;
if (n <= p->s[i].child)
return get_nth(bt, p->s[i].next, n , key, u);
n-= p->s[i].child;
i++;
}
if (n == 1)
goto l1;
return get_nth(bt, p->s[i].next, n-1 , key, u);
}
void
task2(intptr_t exinf)
{
ID tskid;
ER_UINT ercd;
uint_t load;
check_point(7);
ercd = get_lod(TPRI_SELF, &load);
check_ercd(ercd, E_OK);
check_assert(load == 3U);
ercd = get_nth(TPRI_SELF, 0U, &tskid);
check_ercd(ercd, E_OK);
check_assert(tskid == TASK2);
check_point(8);
ercd = slp_tsk();
check_ercd(ercd, E_OK);
check_point(17);
ercd = get_lod(TPRI_SELF, &load);
check_ercd(ercd, E_OK);
check_assert(load == 1U);
check_point(18);
ercd = chg_pri(TASK5, MID_PRIORITY);
check_ercd(ercd, E_OK);
ercd = get_lod(TPRI_SELF, &load);
check_ercd(ercd, E_OK);
check_assert(load == 2U);
ercd = rot_rdq(TPRI_SELF);
check_ercd(ercd, E_OK);
check_point(0);
}
//-----------------------------------------------
// encode()
// PreConditions:
// - letter_to_encode is a letter of the English
// alphabet. It can be small or capital
// PostConditions:
// - encodedvalue will be returned. It is an
// index value in the DOI where the first letter
// of the encodedvalue word is the letter_to_encode
//-----------------------------------------------
int BCipher::encode (char letter_to_encode)
{
int numoccurrences, encodedvalue, randval;
// work with caps only for internal comparisons
if ((letter_to_encode >= ASCIIa) &&
(letter_to_encode <= ASCIIz)) letter_to_encode -= TOCAPITAL;
//spot = letter_to_encode - ASCIIA;
numoccurrences = lettercount[letter_to_encode - ASCIIA];
// Prepare to select a random word in the DOI that
// begins with the letter_to_encode
if (numoccurrences > 1) randval = (rand() % numoccurrences) + 1;
else randval = 1;
// go get the index position of the nth occurrence
// of the letter_to_encode
encodedvalue = get_nth(randval, letter_to_encode);
return(encodedvalue);
} // end encode()
void
task4(intptr_t exinf)
{
ID tskid;
ER_UINT ercd;
uint_t load;
check_point(11);
ercd = get_lod(TPRI_SELF, &load);
check_ercd(ercd, E_OK);
check_assert(load == 1U);
ercd = get_nth(TPRI_SELF, 0U, &tskid);
check_ercd(ercd, E_OK);
check_assert(tskid == TASK4);
check_point(12);
ercd = slp_tsk();
check_ercd(ercd, E_OK);
check_point(0);
}
void
task5(intptr_t exinf)
{
ID tskid;
ER_UINT ercd;
uint_t load;
check_point(13);
ercd = get_lod(TPRI_SELF, &load);
check_ercd(ercd, E_OK);
check_assert(load == 1U);
ercd = get_nth(TPRI_SELF, 0U, &tskid);
check_ercd(ercd, E_OK);
check_assert(tskid == TASK5);
check_point(14);
ercd = loc_mtx(MTX1);
check_ercd(ercd, E_OK);
ercd = get_lod(TPRI_SELF, &load);
check_ercd(ercd, E_OK);
check_assert(load == 0U);
ercd = get_nth(TPRI_SELF, 0U, &tskid);
check_ercd(ercd, E_OK);
check_assert(tskid == TSK_NONE);
ercd = get_lod(MID_PRIORITY, &load);
check_ercd(ercd, E_OK);
check_assert(load == 1U);
ercd = get_nth(MID_PRIORITY, 0U, &tskid);
check_ercd(ercd, E_OK);
check_assert(tskid == TASK5);
check_point(15);
ercd = wup_tsk(TASK2);
check_ercd(ercd, E_OK);
ercd = get_lod(TPRI_SELF, &load);
check_ercd(ercd, E_OK);
check_assert(load == 0U);
ercd = get_lod(MID_PRIORITY, &load);
check_ercd(ercd, E_OK);
check_assert(load == 2U);
check_point(16);
ercd = unl_mtx(MTX1);
check_ercd(ercd, E_OK);
check_point(19);
ercd = get_lod(TPRI_SELF, &load);
check_ercd(ercd, E_OK);
check_assert(load == 2U);
ercd = get_nth(TPRI_SELF, 0U, &tskid);
check_ercd(ercd, E_OK);
check_assert(tskid == TASK5);
check_finish(20);
check_point(0);
}
void
task1(intptr_t exinf)
{
ID tskid;
ER_UINT ercd;
uint_t load;
test_start(__FILE__);
check_point(1);
ercd = get_lod(TMIN_TPRI-2, &load);
check_ercd(ercd, E_PAR);
ercd = get_lod(TMAX_TPRI+1, &load);
check_ercd(ercd, E_PAR);
ercd = get_nth(TMIN_TPRI-2, 0U, &tskid);
check_ercd(ercd, E_PAR);
ercd = get_nth(TMAX_TPRI+1, 0U, &tskid);
check_ercd(ercd, E_PAR);
check_point(2);
ercd = get_lod(MID_PRIORITY, &load);
check_ercd(ercd, E_OK);
check_assert(load == 0U);
ercd = get_nth(MID_PRIORITY, 0U, &tskid);
check_ercd(ercd, E_OK);
check_assert(tskid == TSK_NONE);
check_point(3);
ercd = act_tsk(TASK2);
check_ercd(ercd, E_OK);
ercd = get_lod(MID_PRIORITY, &load);
check_ercd(ercd, E_OK);
check_assert(load == 1U);
ercd = get_nth(MID_PRIORITY, 0U, &tskid);
check_ercd(ercd, E_OK);
check_assert(tskid == TASK2);
ercd = get_nth(MID_PRIORITY, 1U, &tskid);
check_ercd(ercd, E_OK);
check_assert(tskid == TSK_NONE);
check_point(4);
ercd = act_tsk(TASK3);
check_ercd(ercd, E_OK);
ercd = act_tsk(TASK4);
check_ercd(ercd, E_OK);
ercd = get_lod(MID_PRIORITY, &load);
check_ercd(ercd, E_OK);
check_assert(load == 3U);
ercd = get_nth(MID_PRIORITY, 0U, &tskid);
check_ercd(ercd, E_OK);
check_assert(tskid == TASK2);
ercd = get_nth(MID_PRIORITY, 1U, &tskid);
check_ercd(ercd, E_OK);
check_assert(tskid == TASK3);
ercd = get_nth(MID_PRIORITY, 2U, &tskid);
check_ercd(ercd, E_OK);
check_assert(tskid == TASK4);
ercd = get_nth(MID_PRIORITY, 3U, &tskid);
check_ercd(ercd, E_OK);
check_assert(tskid == TSK_NONE);
check_point(5);
ercd = act_tsk(TASK5);
check_ercd(ercd, E_OK);
ercd = get_lod(MID_PRIORITY, &load);
check_ercd(ercd, E_OK);
check_assert(load == 3U);
check_point(6);
ercd = slp_tsk();
check_ercd(ercd, E_OK);
check_point(0);
}
