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func check(_ encoded: String, _ keyValue: String) -> Bool {
    var b = Array(encoded.utf8)
    var k = Array(keyValue.utf8)
    var r0, r1, r2, r3: UInt8
    for i in 0...(b.count-4) {
        (r0, r1, r2, r3) = (b[i], b[i+1], b[i+2], b[i+3])
        b[i+0]=r2^((k[0]+(r0>>4))&0xff)
        b[i+1]=r3^((k[1]+(r1>>2))&0xff)
        b[i+2]=r0^k[2]
        b[i+3]=r1^k[3]
        (k[0], k[1], k[2], k[3]) = (k[1], k[2], k[3], k[0])
    }


    return b == [88, 35, 88, 225, 7, 201, 57, 94, 77, 56, 75, 168, 72, 218, 64, 91, 16, 101, 32, 207, 73, 130, 74, 128, 76, 201, 16, 248, 41, 205, 103, 84, 91, 99, 79, 202, 22, 131, 63, 255, 20, 16]
}
if CommandLine.arguments.count >= 2 {
    let data = CommandLine.arguments[1]
    let key = "345y"
    let result = check(data, key)
    print(result)
}

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func recheck(_ keyValue: String) {
    var b: [UInt8]=[88, 35, 88, 225, 7, 201, 57, 94, 77, 56, 75, 168, 72, 218, 64, 91, 16, 101, 32, 207, 73, 130, 74, 128, 76, 201, 16, 248, 41, 205, 103, 84, 91, 99, 79, 202, 22, 131, 63, 255, 20, 16]
    var k = Array(keyValue.utf8)
    var r0, r1, r2, r3: UInt8
    for _ in 0...38 {
        (k[0], k[1], k[2], k[3]) = (k[1], k[2], k[3], k[0])
    }
    for i in stride(from: 38, to: -1, by: -1) {
        (k[3], k[2], k[1], k[0]) = (k[2], k[1], k[0], k[3])


        r0 = b[i + 2] ^ k[2]
        r1 = b[i + 3] ^ k[3]
        r2 = b[i + 0] ^ ((k[0] + (r0 >> 4)) & 0xff);
        r3 = b[i + 1] ^ ((k[1] + (r1 >> 2)) & 0xff);


        (b[i], b[i+1], b[i+2], b[i+3]) = (r0, r1, r2, r3)
    }
    let string = String(decoding: b, as: UTF8.self)
        print(string)
}


let key = "345y"
recheck(key)