User:PerryTachett

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I am an editor who reads the works of Terry Pratchett. I am also an editor who only just realized I misspelled my user name. (It should be PerryTatchett)

I like doing anti-vandalism, and am keeping a counter of my reverted vandalisms:

Vandalisms Reverted so far: 2

Well, thats about it.

PerryHash-2 is a hash algorithm of my own devising. To calculate a PerryHash-2 Hashsum: (Pseudocode)

array bitbudge, shifts, chunks
string message, data, value, olddata
int roundnum, count
bitbudge := 49, 199, 3, 60, 80, 161, 187, 201, 161, 85, 175, 43, 113, 186, 218, 236, 27, 224, 98,
 220, 203, 241, 137, 198, 100, 215, 71, 214, 54, 21, 244, 139, 178, 107, 164, 28, 88, 126, 235, 27,
 52, 59, 194, 176, 112, 208, 21, 198, 198, 61, 42, 239, 147, 119, 87, 129, 223, 140, 157, 86, 157,
 216, 173, 189, 116, 191, 56, 1, 216, 155, 23, 101, 112, 148, 75, 43, 204, 162, 129, 13, 204, 143,
 25, 218, 40, 129, 223, 107, 42, 51, 201, 239, 33, 5, 24, 76, 176, 98, 37, 125, 192, 114, 185, 220,
 102, 49, 162, 42, 206, 69, 15, 135, 199, 112, 137, 151, 236, 77, 165, 84, 238, 25, 91, 47, 216,
 147, 169, 85
shifts := 35, 25, 99, 127, 121, 74, 66, 59, 78, 42
message := message + "1" + string(length(message))
chunks := 128 bit chunks of message
chunks := reverse(array)
pad chunks[0] to 128 bits with 0
olddata := character(0) repeated 16 times
for data in chunks
    data := data xor olddata
    for roundnum from 0 to 119
        count := 0
        for value in data
            value := value xor bitbudge[count mod 256]
            shifts[count mod length(shifts)] := shifts[count mod length(shifts)] xor value
            shifts[count mod length(shifts)] := shifts[count mod length(shifts)] mod length(bitbudge)
            count := (count + 1) mod length(bitbudge)
        count := 0
        repeat 7
            bitbudge[0] := bitbudge[0] xor data[count]
            shift bitbudge left wrapping around
            count := (count + 3) mod length(data)
        count := 0
        repeat 3
            data[0] := data[0] xor bitbudge[count]
            shift bitbudge left wrapping around
            count := (count - 3) mod length(bitbudge)
        if (roundnum mod 10) == 0
            bitbudge := reverse(bitbudge)
        if (roundnum mod 10) == 5
            data := reverse(data)
        if (roundnum mod 10) == 8
            for value in shifts
                move bitbudge[value] to end
        if (roundnum mod 10) == 3
            for value in shifts
                move data[value] to end
    olddata := data
hashsum := data

Some PerryHash-2 hashes:

PH2("")
= de77bdfb 70b02989 0a3a570c 8e334e82

PH2("the quick brown fox jumps over the lazy dog")
= 13b61e2c ad0085fb ebd7ef84 8fdcf773

PH2("the quick brown fox jumps over the lazy cog")
= 749f9d2c 8550f0b6 f69d3079 fe34a4df