import hashlib
import math
import struct
def mystery(x):
# accept int/float/str only
if not isinstance(x, (int, float, str)):
return False
# canonicalize to bytes in a slightly non-obvious way
if isinstance(x, str):
s = x
elif isinstance(x, float):
# Use exact IEEE-754 payload, not decimal text
s = struct.pack(">d", x).hex()
else: # int
# Mix representation bases and a sign marker
s = (hex(x) + "|" + oct(x) + "|" + bin(x) + "|" + ("-" if x < 0 else "+"))
b = s.encode("utf-8")
# "noise" computations to obscure intent but deterministic
h1 = hashlib.sha256(b).hexdigest()
h2 = hashlib.blake2s(b, digest_size=16, person=b"mystery").hexdigest()
h = (h1 + h2).encode("ascii")
# derive a small checksum-like value
acc = 0
for i, ch in enumerate(h):
acc = (acc * 257 + ch + i) % 1000003
# hidden target condition: very sparse
# additionally require a property of the original string/representation length
L = len(s)
return (acc == 846177) and (L % 7 == 3) and (sum(b) % 97 == 11)
import hashlib
def mystery(x):
# accepts only basic scalar types
if not isinstance(x, (int, float, str)):
return False
# only integers can possibly pass
if not isinstance(x, int):
return False
MASK = (1 << 64) - 1
# 64-bit affine mixing (forces wraparound behavior)
B = 0x9E3779B97F4A7C15
K = 0xD6E8FEB86659FD93
# "normalize" into 64-bit space
u = (x + B) & MASK
b = u.to_bytes(8, "big")
kbytes = K.to_bytes(8, "big")
# bytewise whitening with position-dependent salt
c = []
for i, bi in enumerate(b):
pi = (i * 37 + 11) & 0xFF
ci = bi ^ kbytes[i] ^ pi
c.append(ci)
# decoy constraints (still required)
if (sum(c) % 251) != 42:
return False
acc = 0
for i, ci in enumerate(c):
acc = (acc * 131 + ci + i) % 10007
if acc != 1641:
return False
# sparse extraction; most candidates will leave some bytes behind
payload = bytes(
ci for i, ci in enumerate(c)
if (((ci ^ ((i * 0x11) & 0xFF)) & 0xF0) == 0xA0)
)
# cryptographic "certificate" of the payload
return (
hashlib.md5(payload).hexdigest()
== "d41d8cd98f00b204e9800998ecf8427e"
and hashlib.sha1(payload).hexdigest()
== "da39a3ee5e6b4b0d3255bfef95601890afd80709"
and hashlib.sha256(payload).hexdigest()
== "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"
)
import hashlib
import struct
import math
def mystery(x):
# accept only int/float/str
if not isinstance(x, (int, float, str)):
return False
# canonicalize to bytes in a non-obvious, type-dependent way
if isinstance(x, str):
b = x.encode("utf-8", "surrogatepass")
tag = b"S"
elif isinstance(x, int):
# fixed-width two's-complement-ish encoding (wrap to 128 bits)
u = x & ((1 << 128) - 1)
b = u.to_bytes(16, "big", signed=False)
tag = b"I"
else: # float
# exact IEEE-754 payload
b = struct.pack(">d", float(x))
tag = b"F"
# deterministic "mix" step to obscure what's checked
h = hashlib.sha256(tag + b).digest()
h2 = hashlib.blake2s(h, digest_size=16, person=b"mystery").digest()
# decoy arithmetic constraints (must pass)
s = sum(h2)
if (s % 97) != 0:
return False
if ((h2[0] ^ h2[-1]) & 0x0F) != 0:
return False
# hidden core: accept exactly when the derived payload is empty
payload = bytes(bb for i, bb in enumerate(h2) if ((bb + i) & 0x07) == 1)
# cryptographic certificate of emptiness (hard to reverse directly)
return (
hashlib.md5(payload).hexdigest() == "d41d8cd98f00b204e9800998ecf8427e"
and hashlib.sha1(payload).hexdigest() == "da39a3ee5e6b4b0d3255bfef95601890afd80709"
and hashlib.sha256(payload).hexdigest() == "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"
)
import hashlib
def mystery(x):
# Accept only int/float/str (as promised), but only a non-bool int can pass.
if not isinstance(x, (int, float, str)):
return False
if not isinstance(x, int) or isinstance(x, bool):
return False
MASK = (1 << 128) - 1
def rotl8(v, r):
r &= 7
if r == 0:
return v & 0xFF
return ((v << r) | (v >> (8 - r))) & 0xFF
# 16-byte whitening constants (not meant to be "nice")
K = bytes([0xA6, 0x1D, 0xB7, 0x3C, 0x5A, 0xE1, 0x09, 0xD4,
0x6F, 0x88, 0x12, 0xFE, 0x45, 0x57, 0xC3, 0x2B])
A = bytes([0x13, 0x77, 0x0B, 0xC8, 0x5D, 0x2A, 0x91, 0x04,
0xEE, 0x60, 0x39, 0xAF, 0xD0, 0x1C, 0x82, 0xF6])
# A fixed permutation and rotation schedule
P = [11, 3, 14, 8, 0, 13, 6, 9, 1, 12, 5, 15, 2, 7, 10, 4]
R = [((i * 5 + 1) & 7) for i in range(16)]
# Canonicalize into 16 bytes (wrap in 128-bit space)
u = x & MASK
b = u.to_bytes(16, "big", signed=False)
# Whitening
c = [(((b[i] ^ K[i]) + A[i]) & 0xFF) for i in range(16)]
# Permute + rotate
e = [c[P[i]] for i in range(16)]
d = [rotl8(e[i], R[i]) for i in range(16)]
# Decoy gates (still required)
if (sum(d) % 251) != 250:
return False
xo = 0
for v in d:
xo ^= v
if xo != 178:
return False
# Hidden extraction (sparse, value-dependent)
MAGIC = {0x74, 0x85, 0x96}
payload = []
for i, di in enumerate(d):
s = (41 * i + 17) & 0xFF
pb = di ^ s
if (((pb * 17 + 3) & 0xFF) in MAGIC):
payload.append(pb)
payload = bytes(payload)
# Payload certificate (forces payload == b"abc")
return (
len(payload) == 3
and hashlib.md5(payload).hexdigest() == "900150983cd24fb0d6963f7d28e17f72"
and hashlib.sha1(payload).hexdigest() == "a9993e364706816aba3e25717850c26c9cd0d89d"
and hashlib.sha256(payload).hexdigest() == "ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad"
)
import hashlib
import struct
def mystery(x):
# x may be str or number (int/float). Reject other types (including bytes).
if not isinstance(x, (int, float, str)):
return False
# Canonicalize into bytes in a type-dependent way.
if isinstance(x, str):
b = x.encode("utf-8", "surrogatepass")
tag = b"S"
elif isinstance(x, int):
# fixed 16-byte wrapping (two's-complement-like but unsigned wrap)
u = x & ((1 << 128) - 1)
b = u.to_bytes(16, "big", signed=False)
tag = b"I"
else: # float
# exact IEEE-754 payload plus a one-byte “class” tag
f = float(x)
cls = 0
if f != f:
cls = 3 # NaN
elif f == float("inf") or f == float("-inf"):
cls = 2 # infinity
elif f == 0.0:
cls = 1 # ±0
b = bytes([cls]) + struct.pack(">d", f)
tag = b"F"
# Hash-mix (deterministic but opaque)
h = hashlib.sha256(tag + b).digest()
h2 = hashlib.blake2s(h, digest_size=16, person=b"mystery-v3").digest()
# Decoy constraints (must still pass)
if (h2[0] ^ h2[5] ^ h2[10] ^ h2[15]) != 0x7A:
return False
if (sum(h2) % 97) != 31:
return False
# Extract a "payload" under a masked predicate
payload = bytes(v for i, v in enumerate(h2) if (((v + 13*i) ^ (i*29)) & 7) == 0)
# Certificate: accept only when payload is empty (hard to target directly)
return (
hashlib.md5(payload).hexdigest() == "d41d8cd98f00b204e9800998ecf8427e"
and hashlib.sha1(payload).hexdigest() == "da39a3ee5e6b4b0d3255bfef95601890afd80709"
and hashlib.sha256(payload).hexdigest() == "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"
)
def mystery(x):
import struct
if not isinstance(x, (int, float, str)) or isinstance(x, bool):
return False
# Canonicalize into 8 bytes + a one-byte tag (different per type).
if isinstance(x, int):
if x < 0 or x >= (1 << 64):
return False
b = x.to_bytes(8, "big")
tag = 0x49
elif isinstance(x, float):
b = struct.pack(">d", float(x))
tag = 0x46
else: # str
s = x.encode("utf-8", "surrogatepass")
# small, deterministic fold to 8 bytes (not cryptographic; just obfuscation)
acc = [0xA5, 0x5A, 0xC3, 0x3C, 0x96, 0x69, 0x0F, 0xF0]
for i, ch in enumerate(s):
j = i & 7
acc[j] = ((acc[j] + ch + (i * 17)) ^ ((ch << (i & 3)) & 0xFF)) & 0xFF
b = bytes(acc)
tag = 0x53
K = (0xA3, 0x1F, 0xC7, 0x55, 0x92, 0x0D, 0xE4, 0x38)
A = (0x11, 0xDE, 0x03, 0xC7, 0x58, 0x29, 0x82, 0x07)
P = (2, 5, 1, 7, 0, 6, 3, 4)
R = (1, 3, 5, 7, 2, 4, 6, 0)
def rotl8(v, r):
r &= 7
return ((v << r) | (v >> (8 - r))) & 0xFF if r else (v & 0xFF)
t = [(b[i] ^ K[i]) & 0xFF for i in range(8)]
u = [t[P[i]] for i in range(8)]
v = [(u[i] + A[i]) & 0xFF for i in range(8)]
w = bytes(rotl8(v[i], R[i]) for i in range(8))
# decoy-ish gates (still required)
if ((tag ^ 0x1C) != 0x55):
return False
if (sum(w) & 0xFF) != 0x3E:
return False
if ((w[1] * w[2] + w[3]) % 257) != 153:
return False
if (((w[4] << 8) | w[5]) ^ ((w[6] << 8) | w[7])) != 0x1C53:
return False
if (w[0] ^ w[2] ^ w[4] ^ w[6]) != 0x02:
return False
expected = (0x6D79737465727921).to_bytes(8, "big")
return w == expected
def mystery(x):
import hashlib
import struct
# Accept only int/float/str (and reject bool explicitly).
if not isinstance(x, (int, float, str)) or isinstance(x, bool):
return False
# Type-tagged canonicalization to bytes (designed to be non-obvious).
if isinstance(x, str):
b = x.encode("utf-8", "surrogatepass")
tag = b"S"
elif isinstance(x, int):
# 96-bit wrap, then add a salt-like nibble derived from popcount.
u = x & ((1 << 96) - 1)
pc = u.bit_count() & 0x0F
b = bytes([pc]) + u.to_bytes(12, "big")
tag = b"I"
else: # float
f = float(x)
# normalize -0.0 to +0.0 in a sneaky way
if f == 0.0:
f = 0.0
b = struct.pack(">d", f)
tag = b"F"
# Hash mixing with personalization (opaque to reverse).
h = hashlib.blake2s(tag + b, digest_size=32, person=b"mystery-game").digest()
g = hashlib.sha256(h + tag).digest()
# Decoy arithmetic gates (still required).
if ((h[0] ^ h[7] ^ h[13] ^ h[31]) & 0xFF) != 0xA6:
return False
if (sum(g) % 251) != 17:
return False
# Extract a "payload" under a predicate depending on both hashes.
payload = bytearray()
for i in range(32):
v = h[i] ^ g[31 - i] ^ ((i * 73 + 19) & 0xFF)
if (v & 0x0F) == ((h[(i * 5) & 31] + i) & 0x0F):
payload.append(v)
payload = bytes(payload)
# Certificate: accept only when payload hashes to the empty-string digests,
# i.e., when payload == b"" (but that's hard to hit while also passing gates).
return (
hashlib.md5(payload).hexdigest() == "d41d8cd98f00b204e9800998ecf8427e"
and hashlib.sha1(payload).hexdigest() == "da39a3ee5e6b4b0d3255bfef95601890afd80709"
and hashlib.sha256(payload).hexdigest() == "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"
)
def mystery(x):
# x may be str or number, but only one very specific 64-bit integer can pass.
if not isinstance(x, (int, float, str)) or isinstance(x, bool):
return False
if not isinstance(x, int):
return False
if x < 0 or x >= (1 << 64):
return False
MASK = (1 << 64) - 1
def _rotl64(v, r):
r &= 63
return ((v << r) | (v >> (64 - r))) & MASK if r else (v & MASK)
# Bijective mixer (built from invertible operations in 64-bit space).
def _mix64(u):
u &= MASK
u ^= (u >> 30)
u = (u * 0xBF58476D1CE4E5B9) & MASK
u ^= (u >> 27)
u = (u * 0x94D049BB133111EB) & MASK
u ^= (u >> 31)
return u & MASK
# A bijection (Gray-code transform), to add another reversible layer.
def _t(u):
u &= MASK
return (u ^ (u >> 1)) & MASK
# Hidden 64-bit target, reconstructed from an obfuscated blob.
def _secret_x():
obf = 0x226AD27A02CA729A
b = obf.to_bytes(8, "big")
# Key is generated (not stored directly), but is fully deterministic.
k = bytes((((i * 73 + 41) & 0xFF) ^ 0xAA) for i in range(8))
p = bytes((b[i] ^ k[i]) for i in range(8))
return int.from_bytes(p, "big") # 64-bit
sec = _secret_x()
# Salt and some noisy-but-deterministic “structure” checks.
SALT = 0xD1B54A32D192ED03
m = _mix64((_t(x) + SALT) & MASK)
exp = _mix64((_t(sec) + SALT) & MASK)
# Decoy-ish gates (must still pass).
mb = m.to_bytes(8, "big")
xb = x.to_bytes(8, "big")
# A couple of constraints that look independent, but are tuned to the same target.
if ((sum(mb) + 17 * mb[0] + 31 * mb[7]) % 251) != ((sum(exp.to_bytes(8, "big")) + 17 * ((exp >> 56) & 0xFF) + 31 * (exp & 0xFF)) % 251):
return False
if (((_rotl64(m, 19) ^ m) & 0xFFFF) != ((_rotl64(exp, 19) ^ exp) & 0xFFFF)):
return False
if (((xb[1] ^ xb[3] ^ xb[5] ^ xb[7]) & 0xFF) != ((sec.to_bytes(8, "big")[1] ^ sec.to_bytes(8, "big")[3] ^ sec.to_bytes(8, "big")[5] ^ sec.to_bytes(8, "big")[7]) & 0xFF)):
return False
# Core check (written in a slightly disguised way).
return ((m - exp) & MASK) == 0
def mystery(x):
import hashlib
import struct
# Only allow int/float/str (reject bool explicitly).
if not isinstance(x, (int, float, str)) or isinstance(x, bool):
return False
# Canonicalize to bytes in a type-dependent, slightly sneaky way.
if isinstance(x, str):
b = x.encode("utf-8", "surrogatepass")
tag = b"S"
elif isinstance(x, float):
# Exact IEEE-754 bytes, plus a classifier byte.
f = float(x)
if f != f:
cls = 3 # NaN
elif f == float("inf") or f == float("-inf"):
cls = 2 # inf
elif f == 0.0:
cls = 1 # ±0
f = 0.0 # normalize -0.0 to +0.0
else:
cls = 0
b = bytes([cls]) + struct.pack(">d", f)
tag = b"F"
else: # int
# 128-bit wrap with a popcount nibble header.
u = x & ((1 << 128) - 1)
b = bytes([(u.bit_count() * 11 + 7) & 0xFF]) + u.to_bytes(16, "big")
tag = b"I"
# Opaque mixing
h = hashlib.blake2s(tag + b, digest_size=32, person=b"game:mystery:2026").digest()
g = hashlib.sha256(h + tag + bytes([len(b) & 0xFF])).digest()
# Decoy gates (still required)
if ((h[0] + 3*h[11] + 5*h[23] + 7*h[31]) % 257) != 42:
return False
if ((g[2] ^ g[5] ^ g[8] ^ g[13] ^ g[21] ^ g[34 % 32]) & 0xFF) != 0xA7:
return False
# Sparse extraction predicate; goal is to make payload empty.
payload = bytearray()
for i in range(32):
v = (h[i] + (g[31 - i] ^ ((i * 73 + 19) & 0xFF))) & 0xFF
if ((v ^ (h[(i * 7) & 31] + i)) & 0x0F) == 0:
payload.append(v)
payload = bytes(payload)
# Accept only if payload is exactly empty (proved by standard empty digests).
return (
hashlib.md5(payload).hexdigest() == "d41d8cd98f00b204e9800998ecf8427e"
and hashlib.sha1(payload).hexdigest() == "da39a3ee5e6b4b0d3255bfef95601890afd80709"
and hashlib.sha256(payload).hexdigest() == "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"
)
def mystery(x):
# Accept only int/float/str (explicitly reject bool).
if not isinstance(x, (int, float, str)) or isinstance(x, bool):
return False
# Canonicalize x -> y (64-bit unsigned int), with type-dependent quirks.
if isinstance(x, int):
y = x
elif isinstance(x, float):
# Only allow floats that are *exactly* integral.
if x != x or x in (float("inf"), float("-inf")):
return False
if not x.is_integer():
return False
y = int(x)
else: # str
s = x.strip()
# Allow base-prefix forms too (0x..., 0o..., 0b...).
try:
y = int(s, 0)
except Exception:
return False
# Restrict to 64-bit unsigned space.
if y < 0 or y >= (1 << 64):
return False
MASK64 = (1 << 64) - 1
MASK32 = (1 << 32) - 1
def rotl64(v, r):
r &= 63
v &= MASK64
return ((v << r) | (v >> (64 - r))) & MASK64 if r else v
def _keys():
# Deterministic "PRNG-ish" 32-bit key schedule.
z = 0xC3A5C85C # fixed seed
out = []
for i in range(6):
# xorshift32
z ^= (z << 13) & MASK32
z ^= (z >> 17) & MASK32
z ^= (z << 5) & MASK32
# round key with some extra whitening
k = (z + (0x9E3779B9 * (i + 1))) & MASK32
k ^= ((k << 7) & MASK32)
out.append(k & MASK32)
return out
def _F(r, k):
# 32-bit mixing function (nonlinear, but used in a Feistel network).
r = (r + k) & MASK32
r ^= (r >> 16)
r = (r * 0x7FEB352D) & MASK32
r ^= (r >> 15)
r = (r * 0x846CA68B) & MASK32
r ^= (r >> 16)
return r & MASK32
def _feistel64(u):
# 64-bit Feistel permutation (6 rounds).
L = (u >> 32) & MASK32
R = u & MASK32
for k in _keys():
L, R = R, (L ^ _F(R, k)) & MASK32
return ((L << 32) | R) & MASK64
def _secret():
# Secret 8 bytes reconstructed from two "innocent looking" tables.
a = (0x13, 0x57, 0x9B, 0xDF, 0x21, 0x88, 0x70, 0x0C)
b = (0xA7, 0x2D, 0x87, 0x3C, 0xB1, 0xA5, 0x86, 0x54)
p = bytes((a[i] ^ b[i]) & 0xFF for i in range(8))
# Add reversible "noise" steps that ultimately cancel out.
q = bytes((p[i] + ((17 * i) & 0xFF)) & 0xFF for i in range(8))
r = bytes((q[i] - ((17 * i) & 0xFF)) & 0xFF for i in range(8))
# Another reversible shuffle (net effect: identity).
t = r[3:] + r[:3]
u = t[-3:] + t[:-3]
return int.from_bytes(u, "big") # 64-bit
sec = _secret()
m = _feistel64(y)
t = _feistel64(sec)
# Several gates that look independent, but are all tuned to the same hidden target.
mb = m.to_bytes(8, "big")
tb = t.to_bytes(8, "big")
if (sum(mb) + 11 * mb[0] + 23 * mb[7]) % 251 != (sum(tb) + 11 * tb[0] + 23 * tb[7]) % 251:
return False
def poly257(bs):
acc = 0
for i, v in enumerate(bs):
acc = (acc * 257 + v + (19 * i)) % 65521
return acc
if poly257(mb) != poly257(tb):
return False
def sig64(v):
v &= MASK64
return ((v ^ rotl64(v, 7) ^ rotl64(v, 23) ^ 0xA1F1C3D5E7B9D0F2) & 0xFFFF)
if sig64(m) != sig64(t):
return False
# Core check (written in a slightly disguised way).
return ((m - t) & MASK64) == 0