From fe261e2a1ccab87d82209a6784b0e3b9b0004c1b Mon Sep 17 00:00:00 2001
From: "hilder.vitor" <hilder.vitor@gmail.com>
Date: Fri, 11 Mar 2022 12:58:21 +0100
Subject: [PATCH] Created ct_not_const to speed up SchemeNTRU::not_gate

---
 include/ntruhe.h | 9 +++++++++
 src/ntruhe.cpp   | 3 ++-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/include/ntruhe.h b/include/ntruhe.h
index 46eea2b..7eb8ed4 100644
--- a/include/ntruhe.h
+++ b/include/ntruhe.h
@@ -74,6 +74,7 @@ class SchemeNTRU
     Ctxt_NTRU ct_nand_const;
     Ctxt_NTRU ct_and_const;
     Ctxt_NTRU ct_or_const;
+    Ctxt_NTRU ct_not_const;
 
     void mask_constant(Ctxt_NTRU& ct, int constant);
 
@@ -98,6 +99,13 @@ class SchemeNTRU
         //cout << "Encryption of OR: " << float(clock()-start)/CLOCKS_PER_SEC << endl;
     }
 
+    inline void set_not_const()
+    {
+        encrypt(ct_not_const, 1);
+    }
+
+
+
     public:
     
     SchemeNTRU()
@@ -112,6 +120,7 @@ class SchemeNTRU
         set_nand_const();
         set_and_const();
         set_or_const();
+        set_not_const();
     }
     /**
      * Encrypts a bit using matrix NTRU.
diff --git a/src/ntruhe.cpp b/src/ntruhe.cpp
index d4868d4..4862dee 100644
--- a/src/ntruhe.cpp
+++ b/src/ntruhe.cpp
@@ -298,6 +298,7 @@ void SchemeNTRU::xor_gate(Ctxt_NTRU& ct_res, const Ctxt_NTRU& ct1, const Ctxt_NT
 
 void SchemeNTRU::not_gate(Ctxt_NTRU& ct_res, const Ctxt_NTRU& ct) const
 {
-    nand_gate(ct_res, ct, ct);
+    ct_res = ct_not_const;
+    ct_res -= ct;
 }