bool subsetSum(int *arr, int X, int i)
{
if ( i == 0 && arr[i] == X)
return true;
if ( i == 0 && arr[i] != X)
return false;
else
{
return subsetSum(arr,X-arr[i],i-1) || subsetSum(arr,X,i-1);
}
}
int main(){
int x = 0, y = 0, k = 1, i = 0, j = 0;
while(1){
scanf("%d %d %d", &x, &y, &n);
if(!x && !y && !n)
break;
t = 0;
for(i = 1; i <= n; i++){
scanf("%d", &v[i]);
t += v[i];
}
t = (x + y + t);
if(t % 2 != 0){
printf("Teste %d\nN\n\n", k++);
continue;
}
t = (t / 2) - x;
if(subsetSum())
printf("Teste %d\nS\n\n", k++);
else
printf("Teste %d\nN\n\n", k++);
}
return 0;
}
int findTargetSumWays(vector<int>& nums, int S) {
// sum(P) - sum(N) = S
// <=>
// 2 * sum(P) = S + sum(nums)
int sum = accumulate(nums.begin(), nums.end(), 0);
if (sum < S || (S + sum) % 2) {
return 0;
}
return subsetSum(nums, (S + sum) / 2);
}
int main (int argc, char *argv[])
{
// read the data from a file
if (argc < 2)
{
printf("Need input file name\n");
return EXIT_FAILURE;
}
FILE * fptr = fopen(argv[1], "r");
if (fptr == NULL)
{
printf("fopen fail\n");
return EXIT_FAILURE;
}
int numInt = countInteger(fptr);
// go back to the beginning of the file
fseek (fptr, 0, SEEK_SET);
int kval; // the value equal to the sum
if (fscanf(fptr, "%d", & kval) != 1)
{
printf("fscanf error\n");
fclose(fptr);
return EXIT_FAILURE;
}
numInt --; // kval is not part of the set
int * setA = malloc(sizeof(int) * numInt);
int ind = 0;
for (ind = 0; ind < numInt; ind ++)
{
int aval;
if (fscanf(fptr, "%d", & aval) != 1)
{
printf("fscanf error\n");
fclose(fptr);
return EXIT_FAILURE;
}
setA[ind] = aval;
}
fclose (fptr);
if (isValidSet(setA, numInt) == 1)
{
printf("There are %d subsets whose sums are %d\n",
subsetSum(setA, numInt, kval), kval);
}
else
{
printf("Invalid set\n");
}
free(setA);
return EXIT_SUCCESS;
}
void generateSubsetSums(const unsigned target_sum,
const std::vector<IntList> &possibles,
std::vector<IntList> &subsets) {
IntList tuple;
subsetSum(possibles, possibles.size(), tuple, 0, subsets, target_sum, 0);
}
// Given a list of lists of possible cage values:
// [[1,2,3], [3,4,5]]
// Recursively generates tuples of combinations from each of the lists as
// follows:
// [1,3]
// [1,4]
// [1,5]
// [2,3]
// [2,4]
// ... etc
// Each of these is checked against the target sum, and pushed into a result
// vector if they match.
// Note: The algorithm assumes that the list of possibles/candidates are
// ordered. This allows it to bail out early if it detects there's no point
// going further.
static void subsetSum(const std::vector<IntList> &possible_lists,
const std::size_t p_size, IntList &tuple,
unsigned tuple_sum, std::vector<IntList> &subsets,
const unsigned target_sum, unsigned list_idx) {
for (unsigned p = list_idx; p < p_size; ++p) {
for (auto &poss : possible_lists[p]) {
// Optimization for small target sums: if the candidate is bigger than
// the target itself then it can't be valid, neither can any candidate
// after it (ordered).
if (target_sum < static_cast<unsigned>(poss)) {
break;
}
// Can't repeat a value inside a cage
if (std::find(tuple.begin(), tuple.end(), poss) != tuple.end()) {
continue;
}
// Pre-calculate the new tuple values to avoid spurious
// insertions/deletions to the vector.
const auto new_tuple_sum = tuple_sum + poss;
const auto new_tuple_size = tuple.size() + 1;
// If we've added too much then we can bail out (ordered).
if (new_tuple_sum > target_sum) {
break;
}
// If there are fewer spots left in the tuple than there are options for
// the sum to reach the target, bail.
// TODO: This could be more sophisticated (can't have more than one 1, so
// it's more like the N-1 sum that it should be greater than.
if ((p_size - new_tuple_size) > (target_sum - new_tuple_sum)) {
break;
}
if (new_tuple_size == p_size) {
// If we've reached our target size then we can stop searching other
// possiblities from this list (ordered).
if (new_tuple_sum == target_sum) {
tuple.push_back(poss);
subsets.push_back(tuple);
tuple.pop_back();
break;
}
// Else, move on to the next candidate in the list.
continue;
}
tuple_sum += poss;
tuple.push_back(poss);
subsetSum(possible_lists, p_size, tuple, tuple_sum, subsets, target_sum,
p + 1);
tuple.pop_back();
tuple_sum -= poss;
}
}
}
int main(int argc,char *argv[])
{
int arr[] = {1,4,9,2,3};
std::cout << subsetSum(arr,20,4);
}
/* This is the main funtion provided to handle the file I/O and program output
* Please do not modify this function. All neccessary inputs are provided through
* the interface subsetSum, please implement that funtion. */
int main(int argc, char **argv)
{
// Check arguments
if (argc < 4) {
//printf("Usage: pa13 input output <number of threads>\n");
printf("Usage: %s <input_set> <input_num> <output> <number of threads>\n", argv[0]);
return EXIT_FAILURE;
}
FILE * fpset = fopen(argv[1], "r");
FILE * fpnum = fopen(argv[2], "r");
FILE * fptr = fopen(argv[3], "w");
// check if file exist and can be read
if (fpset == NULL) {
fprintf(stderr, "Error opening file %s\n", argv[1]);
return EXIT_FAILURE;
}
if (fpnum == NULL) {
fprintf(stderr, "Error opening file %s\n", argv[2]);
return EXIT_FAILURE;
}
if (fptr == NULL) {
return EXIT_FAILURE;
}
int maxThread = (int) strtol(argv[4], NULL, 10);
int numThread;
int * intset, length, targetSumValue, tmp, cnt;
int bfsize = INIT_SET_SIZE;
intset = (int*) malloc(sizeof(int) * bfsize);
cnt = 0, tmp = 0;
// read set data from formated file input
while ((tmp = fscanf(fpset, "%d\n", intset+cnt)) != EOF) {
if (tmp <= 0) {
fprintf(stderr, "Wrong input format in file %s.\n", argv[1]);
return EXIT_FAILURE;
}
cnt += tmp;
// resize array if actual number of elements is founded to be
// larger than initial size
if (cnt > bfsize) {
bfsize += bfsize;
int * nset = (int*) realloc(intset, sizeof(int) * bfsize);
if (nset == 0) {
fprintf(stderr, "Error allocating memory.\n");
return EXIT_FAILURE;
}
intset = nset;
}
}
length = cnt;
// read N from second file
tmp = fscanf(fpnum, "%d\n", &targetSumValue);
if (tmp <= 0) {
fprintf(stderr, "Wrong input format in file %s.\n", argv[2]);
return EXIT_FAILURE;
}
fclose(fpset);
fclose(fpnum);
long result = 0;
for (numThread = 1; numThread <= maxThread; numThread ++) {
struct timeval Time1;
struct timeval Time2;
gettimeofday(& Time1, NULL);
//result = subsetSum(intset, length, targetSumValue, 1);
result = subsetSum(intset, length, targetSumValue, numThread);
gettimeofday(& Time2, NULL);
printf("%d thread(s), run time: %8.4f\n",
numThread, timeDiff(Time1, Time2));
}
free (intset);
// Write result
fprintf(fptr, "%ld", result);
fclose (fptr);
return EXIT_SUCCESS;
}
