from attractor import row, forced_tail
cp=(0,1,1,1,1,1); p=6
prefixes=["0000010111010001","0100010111010001","1000010111010001","1100010111010001"]
def full_u(pref,nu):
    u=[int(c) for c in pref]
    while len(u)<nu:
        n=len(u)
        for v in (0,1):
            if row(u+[v]+[0]*(nu-n-1),6*n+1)[6*n]==0: u.append(v); break
    return u
def windows(u,K,W=7):
    T=len(u)*p; d=[cp[t%p] for t in range(T+K+2)]
    e=[(u[t//p] if t%p==0 else (1 if t%p==5 else 0)) for t in range(T)]
    prev,cur=d[:T],e; out=[tuple(cur[:W])]
    for k in range(1,K):
        nxt=[cur[t+1]^(cur[t]|prev[t]) for t in range(len(cur)-1)]; prev,cur=cur,nxt; out.append(tuple(cur[:W]))
    return out
nu=24; K=130
U=[full_u(x,nu) for x in prefixes]
print("forced bits beyond u_15 identical for all four?", all(u[16:]==U[0][16:] for u in U))
Wn=[windows(u,K) for u in U]
for i in range(1,4):
    merged=next((k for k in range(1,K-1) if Wn[0][k]==Wn[i][k] and Wn[0][k+1]==Wn[i][k+1]),None)
    print(f"  prefix {i+1} vs prefix 1: windows (nights 0-6) agree at two consecutive depths from lantern {merged+1 if merged is not None else 'never (within range)'}"
          + ("  ->  EXACTLY equivalent forever (certified)" if merged is not None else ""))