PUZZLE #4366: IrisCode Recognition (diff 5)

iris learn difficulty: 5/7 analyze author: system unsolved

Two 256-bit IrisCode vectors are provided. Compute the Hamming distance between them (fraction of differing bits). Answer is the distance as a float.

DATA

Difficulty	`5`
Code1	`0001111111101010011111111101001001111100000111110011110100111000010011011000101011111100011000110000011111110110001100001000110010010111010010111001000110101111001001010001010100011110111011100101000000000011100011101111000000101101100011010111100110100010`
Code2	`1101111010100011011001101011100100111101100011010110100011001100010001101001011001101110000110111111000000100101111000100000000000101101000111111000110011010011001110100110100111001101011100101011101010011111101101000101001010001000011011011111000010011010`
Hint	`IrisCode Hamming distance = count_differing_bits / 256. XOR the two bit vectors and count set bits. Answer = differing_bits/256 as exact decimal (trailing zeros OK, rounding not)`
Answer Format	`exact decimal Hamming distance (0-1) — compute as differing_bits/256 for full precision. trailing zeros optional, rounding rejected`

{
  "type": "iris",
  "difficulty": 5,
  "code1": "0001111111101010011111111101001001111100000111110011110100111000010011011000101011111100011000110000011111110110001100001000110010010111010010111001000110101111001001010001010100011110111011100101000000000011100011101111000000101101100011010111100110100010",
  "code2": "1101111010100011011001101011100100111101100011010110100011001100010001101001011001101110000110111111000000100101111000100000000000101101000111111000110011010011001110100110100111001101011100101011101010011111101101000101001010001000011011011111000010011010",
  "hint": "IrisCode Hamming distance = count_differing_bits / 256. XOR the two bit vectors and count set bits. Answer = differing_bits/256 as exact decimal (trailing zeros OK, rounding not)",
  "answer_format": "exact decimal Hamming distance (0-1) \u2014 compute as differing_bits/256 for full precision. trailing zeros optional, rounding rejected"
}

author's note: Pool fill: iris diff 5