// Multiply a ciphertext vector by a plaintext dense matrix
// and/or build a cache with the multiplication constants
void multilpy(Ctxt* ctxt)
{
RBak bak; bak.save(); ea.getTab().restoreContext();
// idxes describes a genealized diagonal, {(i,idx[i])}_i
// initially just the identity, idx[i]==i
vector<long> idxes(ea.size());
for (long i = 0; i < ea.size(); i++) idxes[i] = i;
// call the recursive procedure to do the actual work
rec_mul(ctxt, 0, 0, idxes);
if (ctxt!=nullptr && res!=nullptr)
*ctxt = *res; // copy the result back to ctxt
// "install" the cache (if needed)
if (buildCache == cachezzX)
mat.installzzxcache(zCache);
else if (buildCache == cacheDCRT)
mat.installDCRTcache(dCache);
}
bool containsNearbyDuplicate(vector<int>& nums, int k) {
if (nums.empty()) {
return false;
}
vector<int> idxes(nums.size());
for (int i=0; i<nums.size(); ++i) {
idxes[i] = i;
}
sort(idxes.begin(), idxes.end(), [&nums](int a, int b) {
return nums[a] < nums[b];
});
int last = nums[idxes[0]];
int last_idx = idxes[0];
for (int i=1; i<idxes.size(); ++i) {
if (last == nums[idxes[i]] && idxes[i] - last_idx <= k) {
return true;
}
last = nums[idxes[i]];
last_idx = idxes[i];
}
return false;
}