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+// Copyright (c) Jupyter Development Team.
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+// Distributed under the terms of the Modified BSD License.
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+
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+// Most of the implementation below is adapted from the following repository:
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+// https://github.com/garycourt/murmurhash-js/blob/master/murmurhash2_gc.js
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+// Which has the following MIT License:
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+//
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+// Copyright (c) 2011 Gary Court
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+// Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"),
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+// to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software,
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+// and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
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+// The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
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+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
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+// TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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+
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+// The implementation below uses case fallthrough as part of the algorithm.
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+/* eslint-disable no-fallthrough */
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+
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+const m = 0x5bd1e995;
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+const encoder = new TextEncoder();
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+
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+/**
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+ * Calculate the murmurhash2 for a given string and seed.
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+ *
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+ * @param str The string to calculate the Murmur2 hash for.
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+ * @param seed The seed.
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+ *
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+ * @returns The Murmurhash2 hash.
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+ */
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+export function murmur2(str: string, seed: number): number {
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+ const data = encoder.encode(str);
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+ let len = data.length;
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+ let h = seed ^ len;
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+ let i = 0;
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+
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+ while (len >= 4) {
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+ let k =
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+ (data[i] & 0xff) |
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+ ((data[++i] & 0xff) << 8) |
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+ ((data[++i] & 0xff) << 16) |
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+ ((data[++i] & 0xff) << 24);
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+
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+ k = (k & 0xffff) * m + ((((k >>> 16) * m) & 0xffff) << 16);
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+ k ^= k >>> 24;
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+ k = (k & 0xffff) * m + ((((k >>> 16) * m) & 0xffff) << 16);
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+
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+ h = ((h & 0xffff) * m + ((((h >>> 16) * m) & 0xffff) << 16)) ^ k;
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+
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+ len -= 4;
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+ ++i;
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+ }
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+
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+ switch (len) {
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+ case 3:
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+ h ^= (data[i + 2] & 0xff) << 16;
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+ case 2:
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+ h ^= (data[i + 1] & 0xff) << 8;
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+ case 1:
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+ h ^= data[i] & 0xff;
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+ h = (h & 0xffff) * m + ((((h >>> 16) * m) & 0xffff) << 16);
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+ }
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+
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+ h ^= h >>> 13;
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+ h = (h & 0xffff) * m + ((((h >>> 16) * m) & 0xffff) << 16);
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+ h ^= h >>> 15;
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+
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+ return h >>> 0;
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+}
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Afshin Taylor Darian