PUZZLE #4795: IrisCode Recognition (diff 6)

iris learn difficulty: 6/7 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	`6`
Code1	`1111011000010110110001110100110100101111001100001101100111011000100100010100001110010001010001111110111111000011010011100111100111010010101000010011101100110111111000101111100110001110000111011000010101000100001010101101001110101001110110001000000101101001`
Code2	`1001010100011000011111110111000110110010111101101000001000011010001001110101011110001000000111111000011111111110101111100010000111111110100001001100100100000010010011010110110100010100010111101000110010010010011101011111101011001101011101111101101110100001`
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": 6,
  "code1": "1111011000010110110001110100110100101111001100001101100111011000100100010100001110010001010001111110111111000011010011100111100111010010101000010011101100110111111000101111100110001110000111011000010101000100001010101101001110101001110110001000000101101001",
  "code2": "1001010100011000011111110111000110110010111101101000001000011010001001110101011110001000000111111000011111111110101111100010000111111110100001001100100100000010010011010110110100010100010111101000110010010010011101011111101011001101011101111101101110100001",
  "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 6