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pub trait Hash {
fn hash(&self) -> usize;
}
impl Hash for &[u8] {
fn hash(&self) -> usize {
murmurHash64A(self, 0xcae4f57) as usize
}
}
pub fn murmurHash64A (key: &[u8], seed: u64) -> u64 {
let m = 0xc6a4a7935bd1e995;
let r = 47;
let mut h = seed ^ ((key.len() as u64).wrapping_mul(m));
let mut i = 0;
let len = key.len() & 7;
let end = key.len() - len;
while i < end {
let mut k = key[i + 0] as u64;
k |= (key[i + 1] as u64) << 8;
k |= (key[i + 2] as u64) << 16;
k |= (key[i + 3] as u64) << 24;
k |= (key[i + 4] as u64) << 32;
k |= (key[i + 5] as u64) << 40;
k |= (key[i + 6] as u64) << 48;
k |= (key[i + 7] as u64) << 56;
k = k.wrapping_mul(m);
k ^= k >> r;
k = k.wrapping_mul(m);
h ^= k;
h = h.wrapping_mul(m);
i += 8;
}
let shifts = [0, 8, 16, 24, 32, 40, 48];
let offsets = [0, 1, 2, 3, 4, 5, 6];
if len != 0 {
for i in 0..len {
let idx = len - i - 1;
h ^= (key[end + offsets[idx]] as u64) << shifts[idx];
}
h = h.wrapping_mul(m);
}
h ^= h >> r;
h = h.wrapping_mul(m);
h ^= h >> r;
h
}