def cmb(n,r,mod):
  if r<0 or r>n:
    return 0
  r=min(r,n-r)
  return g1[n]*g2[r]*g2[n-r]%mod
 
n=int(input())
b=list(map(int,input().split()))
mod=10**9+7

g1=[1,1]
g2=[1,1]
inverse=[0,1]
 
for i in range(2,n+1):
  g1.append((g1[-1]*i)%mod)
  inverse.append((-inverse[mod%i]*(mod//i))%mod)
  g2.append((g2[-1]*inverse[-1])%mod)

for i in range(n):
  if b[i]!=-1:
    b[i]=format(b[i],'032b')
b=[format(0,'032b')]+b

inv2=pow(2,mod-2,mod)
ct=1
ans=1
p=b[0]
for i in range(1,n+1):
  if b[i]==-1:
    ct+=1
  else:
    ct00=0;ct01=0;ct11=0
    for j in range(32):
      if p[j]=='1' and b[i][j]=='0':
        print(0)
        exit()
      elif p[j]=='0' and b[i][j]=='0':
        ct00+=1
      elif p[j]=='0' and b[i][j]=='1':
        ct01+=1
      else:
        ct11+=1
    x=pow(2,ct,mod)
    y=pow(x,ct11,mod)
    z=pow(x-1,ct01,mod)
    a=(y*z%mod)
    for j in range(1,ct+1):
      x*=inv2
      x%=mod
      y=pow(x,ct11,mod)
      z=pow(x-1,ct01,mod)
      w=y*z
      if j%2==1:
        a-=(w*cmb(ct,j,mod)%mod)
      else:
        a+=(w*cmb(ct,j,mod)%mod)
      a%=mod
    ans*=a
    ans%=mod
    ct=1
    p=b[i]
print(ans)