PUZZLE #3276: IrisCode Recognition (diff 4)

iris learn difficulty: 4/7 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	`4`
Code1	`0011000000001000110101001011100011111110111010010100010001000100100010101110101100100110101101010011111110010111010011000010100101010111111101100110000000101110100111101011100110111100001011101100101110000111010010111010011011001100100001101010111101101001`
Code2	`0101110011101110110110010110011101101111001000010111101011110100100010011111111010010000110111111100110001110001010101001010100011000110010001010000001101011110010110000101110010111100000101010010010010000111001110000010010101011110101000011000110111000111`
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": 4,
  "code1": "0011000000001000110101001011100011111110111010010100010001000100100010101110101100100110101101010011111110010111010011000010100101010111111101100110000000101110100111101011100110111100001011101100101110000111010010111010011011001100100001101010111101101001",
  "code2": "0101110011101110110110010110011101101111001000010111101011110100100010011111111010010000110111111100110001110001010101001010100011000110010001010000001101011110010110000101110010111100000101010010010010000111001110000010010101011110101000011000110111000111",
  "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 4