stackexchange.question

curl "https://api.onekey.dev/v1/stackexchange/question?id=11227809" \
  -H "x-api-key: YOUR_API_KEY"

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      "id": "11227809",
      "title": "Why is conditional processing of a sorted array faster than of an unsorted array?",
      "url": "https://stackoverflow.com/questions/11227809/why-is-conditional-processing-of-a-sorted-array-faster-than-of-an-unsorted-array",
      "text": "In this C++ code, sorting the data ( before the timed region) makes the primary loop ~6x faster: #include <algorithm> #include <ctime> #include <iostream> int main() { // Generate data const unsigned arraySize = 32768; int data[arraySize]; for (unsigned c = 0; c < arraySize; ++c) data[c] = std::rand() % 256; // !!! With this, the next loop runs faster. std::sort(data, data + arraySize); // Test clock_t start = clock(); long long sum = 0; for (unsigned i = 0; i < 100000; ++i) { for (unsigned c = 0; c < arraySize; ++c) { // Primary loop. if (data[c] >= 128) sum += data[c]; } } double elapsedTime = static_cast<double>(clock()-start) / CLOCKS_PER_SEC; std::cout << elapsedTime << '\\n'; std::cout << \"sum = \" << sum << '\\n'; } Without std::sort(data, data + arraySize); , the code runs in 11.54 seconds. With the sorted data, the code runs in 1.93 seconds. (Sorting itself takes more time than this one pass over the array, so it's not actually worth doing if we needed to calculate this for an unknown array.) Initially, I thought this might be just a language or compiler anomaly, so I tried Java: imp",
      "createdAt": "2012-06-27T13:51:36Z"
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      "id": "87234",
      "username": "GManNickG",
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