c++ - Efficiency of std::copy vs memcpy -

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इस सवाल का पहले से ही एक उत्तर है: < / P>

  • 8 जवाब

    दक्षता कितना गंभीर है memcpy और std :: copy का उपयोग करने के बीच

    मेरे पास एक ऐसी स्थिति है जहां मेरे सिस्टम पर सदिश कार्यान्वयन परिसीमित स्मृति का उपयोग नहीं करता है, जो कि मुझे :: मेकपीपी (डिस्ट, और वीक [0], आकार) करने के बजाय इसकी सामग्री की प्रतिलिपि बनाना है; मुझे यकीन नहीं है कि यह कितनी बुरी तरह से दक्षता को प्रभावित करने की संभावना है।

    एक उचित सभ्य कार्यान्वयन होगा <

    यदि आपका कार्यान्वयन करता है तो कोड> std :: copy कॉल के लिए संकलित करें memmove उन स्थितियों में जहां यह संभव है (अर्थात तत्व प्रकार एक पीओडी है)।

    संगत भंडारण नहीं है (सी + 03 03 मानक की आवश्यकता है), memmove से std :: copy की तुलना में तेज़ हो सकता है, लेकिन शायद बहुत ज्यादा नहीं। मैं केवल तब ही चिंता करना शुरू कर दूँगा जब आपके पास मापने के लिए माप होना वास्तव में एक मुद्दा है।

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