56 lines
989 B
Go
56 lines
989 B
Go
// File: simple_hash.go
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// Created Time: 2023-06-23
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// Author: Reanon (793584285@qq.com)
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package chapter_hashing
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import "fmt"
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/* Additive hash */
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func addHash(key string) int {
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var hash int64
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var modulus int64
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modulus = 1000000007
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for _, b := range []byte(key) {
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hash = (hash + int64(b)) % modulus
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}
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return int(hash)
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}
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/* Multiplicative hash */
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func mulHash(key string) int {
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var hash int64
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var modulus int64
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modulus = 1000000007
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for _, b := range []byte(key) {
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hash = (31*hash + int64(b)) % modulus
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}
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return int(hash)
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}
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/* XOR hash */
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func xorHash(key string) int {
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hash := 0
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modulus := 1000000007
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for _, b := range []byte(key) {
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fmt.Println(int(b))
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hash ^= int(b)
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hash = (31*hash + int(b)) % modulus
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}
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return hash & modulus
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}
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/* Rotational hash */
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func rotHash(key string) int {
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var hash int64
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var modulus int64
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modulus = 1000000007
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for _, b := range []byte(key) {
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hash = ((hash << 4) ^ (hash >> 28) ^ int64(b)) % modulus
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}
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return int(hash)
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}
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