wehub-resource-sync
49 lines
1.6 KiB
C++
49 lines
1.6 KiB
C++
// Copyright 2025-present the zvec project
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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#include <random>
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#include <set>
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#include <string>
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#include <vector>
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#include <gtest/gtest.h>
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#include <zvec/ailego/hash/crc32c.h>
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#include <zvec/ailego/hash/jump_hash.h>
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#include <zvec/ailego/utility/time_helper.h>
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using namespace zvec::ailego;
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TEST(JumpHash, JumpHash) {
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std::random_device rd;
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std::mt19937 gen(rd());
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std::uniform_int_distribution<uint32_t> dist1(25353195, 25358555);
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std::uniform_int_distribution<uint32_t> dist2(1, 10000);
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std::set<uint32_t> result1;
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std::set<uint32_t> result2;
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const int total = 10000;
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for (int i = 0; i < total; ++i) {
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uint32_t ticket = dist1(gen);
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uint32_t signal = dist2(gen);
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uint64_t key = ((uint64_t)signal << 32) | ticket;
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uint32_t hash1 = (JumpHash(key, 32) << 27) | (ticket & 0x7ffffff);
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uint32_t hash2 = (signal << 27) | (ticket & 0x7ffffff);
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result1.insert(hash1);
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result2.insert(hash2);
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}
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printf("Conflict 1: %f\n", (double)(total - result1.size()) / (double)total);
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printf("Conflict 2: %f\n", (double)(total - result2.size()) / (double)total);
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}
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