61 lines
1.2 KiB
JavaScript
61 lines
1.2 KiB
JavaScript
/**
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* File: simple_hash.js
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* Created Time: 2023-08-06
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* Author: yuan0221 (yl1452491917@gmail.com)
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*/
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/* Additive hash */
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function addHash(key) {
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let hash = 0;
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const MODULUS = 1000000007;
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for (const c of key) {
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hash = (hash + c.charCodeAt(0)) % MODULUS;
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}
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return hash;
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}
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/* Multiplicative hash */
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function mulHash(key) {
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let hash = 0;
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const MODULUS = 1000000007;
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for (const c of key) {
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hash = (31 * hash + c.charCodeAt(0)) % MODULUS;
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}
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return hash;
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}
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/* XOR hash */
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function xorHash(key) {
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let hash = 0;
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const MODULUS = 1000000007;
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for (const c of key) {
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hash ^= c.charCodeAt(0);
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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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function rotHash(key) {
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let hash = 0;
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const MODULUS = 1000000007;
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for (const c of key) {
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hash = ((hash << 4) ^ (hash >> 28) ^ c.charCodeAt(0)) % MODULUS;
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}
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return hash;
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}
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/* Driver Code */
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const key = 'Hello algorithm';
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let hash = addHash(key);
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console.log('Additive hash value is' + hash);
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hash = mulHash(key);
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console.log('Multiplicative hash value is' + hash);
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hash = xorHash(key);
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console.log('XOR hash value is' + hash);
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hash = rotHash(key);
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console.log('Rotational hash value is' + hash);
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