diff --git a/heu/library/algorithms/leichi_paillier/ciphertext.h b/heu/library/algorithms/leichi_paillier/ciphertext.h
index 3044665a..01044f90 100644
--- a/heu/library/algorithms/leichi_paillier/ciphertext.h
+++ b/heu/library/algorithms/leichi_paillier/ciphertext.h
@@ -24,22 +24,15 @@ namespace heu::lib::algorithms::leichi_paillier {
         public:
             BIGNUM* bn_;
         public:
-            // Ciphertext() = default;
             Ciphertext() {
                 bn_ = BN_new();
                 }
             ~Ciphertext(){
                 BN_free(bn_);
-            } //BN_free(bn_);
-
-            // Ciphertext(BIGNUM* res) {bn_ = res;}
-            // Ciphertext(const Ciphertext& other){
-            //     bn_ = other.bn_;
-            // }
+            } 
 
             Ciphertext(const Ciphertext& other) {
                 bn_ = BN_dup(other.bn_);
-                // BN_copy(bn_, other.bn_);
             }
 
             Ciphertext& operator=(const Ciphertext& other) {
@@ -49,7 +42,6 @@ namespace heu::lib::algorithms::leichi_paillier {
                 return *this;
             }
 
-            // explicit Ciphertext(BIGNUM *bn) : bn_(bn){};
             explicit Ciphertext(BIGNUM *bn){ bn_ = bn;}//BN_dup(bn);} 
 
             std::string ToString() const;
diff --git a/heu/library/algorithms/leichi_paillier/vector_encryptor.cc b/heu/library/algorithms/leichi_paillier/vector_encryptor.cc
index 86bf130f..75656a11 100644
--- a/heu/library/algorithms/leichi_paillier/vector_encryptor.cc
+++ b/heu/library/algorithms/leichi_paillier/vector_encryptor.cc
@@ -22,6 +22,10 @@ namespace heu::lib::algorithms::leichi_paillier {
         pt_neg_zero.Set(0);
 
         std::vector<uint8_t> m_flg;
+        for (int64_t i = 0;i<size;i++) 
+        {
+                m_flg.push_back(0);
+        }
         for (int64_t i = 0;i<size;i++) {
             BN_bn2binpad(Plaintext::generateRandom(pk_.n_).bn_,r_bytes+r_offset,BYTECOUNT(pk_.n_.numBits()));
             r_offset += BYTECOUNT(pk_.n_.numBits());
diff --git a/heu/library/benchmark/phe_bench.cc b/heu/library/benchmark/phe_bench.cc
index d31dc57d..08c35d84 100644
--- a/heu/library/benchmark/phe_bench.cc
+++ b/heu/library/benchmark/phe_bench.cc
@@ -82,9 +82,10 @@ class PheBenchmarks {
   void AddCipher(benchmark::State& state) {
     // add (ciphertext + ciphertext)
     const auto& evaluator = he_kit_->GetEvaluator();
+    auto ct = he_kit_->GetEncryptor()->EncryptZero();
     for (auto _ : state) {
-      for (int i = 1; i < kTestSize; ++i) {
-        evaluator->AddInplace(&cts_[0], cts_[i]);
+      for (int i = 0; i < kTestSize; ++i) {
+        evaluator->AddInplace(&ct, cts_[i]);
       }
     }
   }
@@ -92,9 +93,10 @@ class PheBenchmarks {
   void SubCipher(benchmark::State& state) {
     // sub (ciphertext - ciphertext)
     const auto& evaluator = he_kit_->GetEvaluator();
+    auto ct = he_kit_->GetEncryptor()->EncryptZero();
     for (auto _ : state) {
-      for (int i = 1; i < kTestSize; ++i) {
-        evaluator->SubInplace(&cts_[0], cts_[i]);
+      for (int i = 0; i < kTestSize; ++i) {
+        evaluator->SubInplace(&ct, cts_[i]);
       }
     }
   }
@@ -104,7 +106,7 @@ class PheBenchmarks {
     const auto& evaluator = he_kit_->GetEvaluator();
     auto edr = he_kit_->GetEncoder<phe::PlainEncoder>(1);
     for (auto _ : state) {
-      for (int i = 1; i < kTestSize; ++i) {
+      for (int i = 0; i < kTestSize; ++i) {
         evaluator->AddInplace(&cts_[i], edr.Encode(i));
       }
     }
@@ -115,7 +117,7 @@ class PheBenchmarks {
     const auto& evaluator = he_kit_->GetEvaluator();
     auto edr = he_kit_->GetEncoder<phe::PlainEncoder>(1);
     for (auto _ : state) {
-      for (int i = 1; i < kTestSize; ++i) {
+      for (int i = 0; i < kTestSize; ++i) {
         evaluator->SubInplace(&cts_[i], edr.Encode(i));
       }
     }
@@ -125,9 +127,10 @@ class PheBenchmarks {
     // mul (ciphertext * plaintext)
     const auto& evaluator = he_kit_->GetEvaluator();
     auto edr = he_kit_->GetEncoder<phe::PlainEncoder>(1);
+    auto ct = he_kit_->GetEncryptor()->Encrypt(edr.Encode(1));
     for (auto _ : state) {
       for (int i = 1; i < kTestSize; ++i) {
-        evaluator->MulInplace(&cts_[i], edr.Encode(i));
+        evaluator->MulInplace(&ct, edr.Encode(i));
       }
     }
   }