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62 lines
1.2 KiB
62 lines
1.2 KiB
/**
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* File: simple_hash.kt
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* Created Time: 2024-01-25
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* Author: curtishd (1023632660@qq.com)
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*/
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package chapter_hashing
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const val MODULUS = 10_0000_0007
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/* 加法哈希 */
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fun addHash(key: String): Int {
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var hash = 0L
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for (c in key.toCharArray()) {
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hash = (hash + c.code) % MODULUS
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}
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return hash.toInt()
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}
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/* 乘法哈希 */
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fun mulHash(key: String): Int {
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var hash = 0L
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for (c in key.toCharArray()) {
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hash = (31 * hash + c.code) % MODULUS
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}
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return hash.toInt()
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}
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/* 异或哈希 */
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fun xorHash(key: String): Int {
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var hash = 0
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for (c in key.toCharArray()) {
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hash = hash xor c.code
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}
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return hash and MODULUS
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}
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/* 旋转哈希 */
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fun rotHash(key: String): Int {
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var hash = 0L
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for (c in key.toCharArray()) {
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hash = ((hash shl 4) xor (hash shr 28) xor c.code.toLong()) % MODULUS
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}
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return hash.toInt()
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}
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/* Driver Code */
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fun main() {
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val key = "Hello 算法"
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var hash: Int = addHash(key)
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println("加法哈希值为 $hash")
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hash = mulHash(key)
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println("乘法哈希值为 $hash")
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hash = xorHash(key)
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println("异或哈希值为 $hash")
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hash = rotHash(key)
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println("旋转哈希值为 $hash")
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} |