Adapted from: https://asecuritysite.com/encryption/lwe4

Homomorphic-Encryption-Learning-With-Errors-Buchanan.py

# adapted from: https://asecuritysite.com/encryption/lwe4

import sys
import numpy as np
import random
import math

nvals=20
B=[]
e=[]
s = 20
M1 = 5
M2 = 7

q=97

def get_uv(A,B,M,q):
    u=0
    v=0
    sample= random.sample(range(nvals-1), 5)
    print( sample)
    for x in range(0,len(sample)):
      print("[",A[sample[x]],B[sample[x]],"]",)
      u=u+(A[sample[x]])
      v= v+B[sample[x]]
      v=v+math.floor(q/2)*M
    return u%q,v%q

def get_result(u1,v1,u2,v2,q):
   res=((v1-s*u1) + (v2-s*u2)) % q
   if (res>q/2):
    return 1
   return 0

def tobits(val):
   l = [0]*(8)
   l[0]=val & 0x1
   l[1]=(val & 0x2)>>1
   l[2]=(val & 0x4)>>2
   l[3]=(val & 0x8)>>3
   return l

A = random.sample(range(q), nvals)

for x in range(0,len(A)):
    e.append(random.randint(1,3))
    B.append((A[x]*s+e[x])%q)

bits1 = tobits(M1)
bits2 = tobits(M2)

u1_1,v1_1=get_uv(A,B,bits1[0],q)
u2_1,v2_1=get_uv(A,B,bits1[1],q)
u3_1,v3_1=get_uv(A,B,bits1[2],q)
u4_1,v4_1=get_uv(A,B,bits1[3],q)

u1_2,v1_2=get_uv(A,B,bits2[0],q)
u2_2,v2_2=get_uv(A,B,bits2[1],q)
u3_2,v3_2=get_uv(A,B,bits2[2],q)
u4_2,v4_2=get_uv(A,B,bits2[3],q)

get_result(u1_1,v1_1,u1_2,v1_2,q)
get_result(u2_1,v2_1,u2_2,v2_2,q)
get_result(u2_1,v2_1,u2_2,v2_2,q)
get_result(u2_1,v2_1,u2_2,v2_2,q)