void combinationSumHelper(vector<int> &num, int target, int i, vector<int> combination, vector<vector<int> > &result) {
if (target < 0) return;
if (target == 0) {
if (find(result.begin(), result.end(), combination) == result.end())
result.push_back(combination);
return;
}
if (i == num.size()) return;
combinationSumHelper(num, target, i + 1, combination, result);
if ( num[i] <= target ) {
combination.push_back(num[i]);
combinationSumHelper(num, target - num[i], i + 1, combination, result);
}
};
vector<vector<int> > combinationSum(vector<int> &candidates, int target) {
N = candidates.size();
int buf[N];
for (int i = 0; i < N; i++) buf[i] = 0;
combinationSumHelper(0, target, candidates, buf);
sort(ret.begin(), ret.end());
return ret;
}
vector<vector<int> > combinationSum2(vector<int> &num, int target) {
vector<vector<int> > result;
sort(num.begin(), num.end());
if (num[0] > target) return result;
vector<int> combination;
combinationSumHelper(num, target, 0, combination, result);
return result;
};
vector<vector<int>> combinationSum(vector<int>& candidates, int target) {
vector<vector<int>> v;
vector<int> l;
sort(candidates.begin(), candidates.end());
combinationSumHelper(&v, &l, &candidates, 0, target, 0);
return v;
}
vector<vector<int>> SubSetTest::combinationSum( vector<int> num, int target )
{
vector<vector<int>> rst;
if (num.size() == 0)
{
return rst;
}
vector<int> path;
sort(num.begin(), num.end(), less<int>());
combinationSumHelper(num, target, path, 0, rst);
return rst;
}
void combinationSumHelper(vector<vector<int>> * v, vector<int> * l, vector<int> * candidates, int sum, int target, int i) {
if (sum == target && l->size() > 0) {
v->push_back(*l);
return;
}
if (sum > target) {
return;
}
for (int j = i; j < candidates->size(); j++) {
l->push_back( (*candidates)[j] );
combinationSumHelper(v, l, candidates, sum + (*candidates)[j], target, j);
l->pop_back();
}
}
void combinationSumHelper(int pos, int remain, vector<int> &candidates, int buf[]) {
if (remain == 0) {
vector <int> tmp;
for (int i = 0; i < pos; i++) {
for (int j = 0; j < buf[i]; j++) {
tmp.push_back(candidates[i]);
}
}
sort(tmp.begin(), tmp.end());
ret.push_back(tmp);
return;
}
if (pos == N) return;
for (int i = 0; i <= remain / candidates[pos]; i++) {
buf[pos] = i;
combinationSumHelper(pos + 1, remain - i * candidates[pos], candidates, buf);
}
buf[pos] = 0;
}
void SubSetTest::combinationSumHelper( vector<int> num, int target, vector<int> path, int pos, vector<vector<int>>& rst )
{
if (target == 0)
{
rst.push_back(path);
return;
}
int prev = -1;
for (int i = pos; i < num.size(); i++) {
if (num[i] > target) {
break;
}
if (prev != -1 && prev == num[i]) {
continue;
}
path.push_back(num[i]);
combinationSumHelper(num, target - num[i], path, i, rst);
path.pop_back();
prev = num[i];
}
}
