{"id":169,"date":"2021-11-21T12:53:13","date_gmt":"2021-11-21T12:53:13","guid":{"rendered":"http:\/\/47.103.123.166\/?p=169"},"modified":"2021-11-21T12:53:13","modified_gmt":"2021-11-21T12:53:13","slug":"c_3-%e5%ba%93","status":"publish","type":"post","link":"http:\/\/47.103.123.166\/?p=169","title":{"rendered":"C++_3\u2014\u2014\u5e93"},"content":{"rendered":"<p><font face=\"\u6977\u4f53\">&emsp;&emsp;\u8fd9\u4e00\u7cfb\u5217\u6587\u7ae0\u7684\u76ee\u7684\u662f\u5728\u5b66\u4e60\u4e86C++\u57fa\u7840\u540e\uff0c\u7ee7\u7eed\u8865\u5145\u4e00\u4e9bC++\u57fa\u7840\u548c\u8fdb\u9636\u7684\u77e5\u8bc6\u70b9\uff0c\u5305\u62ecC++11\u7684\u76f8\u5173\u5185\u5bb9\u3002<br \/>\n\u4ee5C++11\u6807\u51c6\u4e3a\u57fa\u7840\u3002<\/p>\n<p>C++\u7f51\u7ad9\uff1a<a href=\"http:\/\/www.cplusplus.com\/reference\/\"><a href=\"http:\/\/www.cplusplus.com\/reference\/\">http:\/\/www.cplusplus.com\/reference\/<\/a><\/a><\/p>\n<h3>1 ctime<\/h3>\n<pre><code class=\"language-cpp\">    \/\/\u5305\u542b\u5934\u6587\u4ef6\n    #include &lt;ctime&gt;\n\n    \/\/\u83b7\u53d6\u7cfb\u7edf\u65f6\u95f4\n    clock_t time = clock();\n\n    \/\/\u83b7\u53d6\u7cfb\u7edf\u65f6\u95f4\u5bf9\u5e94\u7684\u79d2\u6570\n    int sec = time\/CLOCKS_PER_SEC;<\/code><\/pre>\n<h3>2 string<\/h3>\n<h4>string value transform<\/h4>\n<pre><code class=\"language-cpp\">    #include &lt;string&gt;\n\n    int std::stoi(const string&amp; str, size_t* idx = 0, int base = 10); \n    int std::stol(const string&amp; str, size_t* idx = 0, int base = 10);\n    int std::stoul(const string&amp; str, size_t* idx = 0, int base = 10);\n    int std::stoll(const string&amp; str, size_t* idx = 0, int base = 10);\n    int std::stoull(const string&amp; str, size_t* idx = 0, int base = 10);\n    int std::stof(const string&amp; str, size_t* idx = 0);\n    int std::stod(const string&amp; str, size_t* idx = 0);\n    int std::stold(const string&amp; str, size_t* idx = 0); \n\n    \/\/ \u4ee5\u4e0b\u65b9\u6cd5 \u4ec5\u4fdd\u75596\u4f4d\u5c0f\u6570\n    string std::to_string (int val);\n    string std::to_string (long val);\n    string std::to_string (long long val);\n    string std::to_string (unsigned val);\n    string std::to_string (unsigned long val);\n    string std::to_string (unsigned long long val);\n    string std::to_string (float val);\n    string std::to_string (double val);\n    string std::to_string (long double val);<\/code><\/pre>\n<h4>Iterators operate<\/h4>\n<pre><code class=\"language-cpp\">    \/\/ \u6b63\u5411\u8fed\u4ee3\u5668\n    iterator begin() noexcept;\n    iterator end() noexcept;\n    \/\/ \u53cd\u5411\u8fed\u4ee3\u5668\n    iterator begin() noexcept;\n    iterator end() noexcept;\n    \/\/ \u5e38\u91cf\u6b63\u5411\u8fed\u4ee3\u5668\n    const_iterator cbegin() noexcept;\n    const_iterator cend() noexcept;\n    \/\/ \u5e38\u91cf\u53cd\u5411\u8fed\u4ee3\u5668\n    const_iterator crbegin() noexcept;\n    const_iterator crend() noexcept;<\/code><\/pre>\n<h4>size &amp; resize &amp; empty &amp; clear<\/h4>\n<pre><code class=\"language-cpp\">    \/\/\n    size_t size() const noexcept;\n    size_t length() const noexcept;\n\n    void resize (size_t n);\n    void resize (size_t n, char c); \/\/ \u7a7a\u95f2\u4f4d\u7f6e\u7528\u5b57\u7b26 c \u8865\u5145\n\n    void clear() noexcept;\n    bool empty() const noexcept;<\/code><\/pre>\n<h4>Element operate<\/h4>\n<pre><code class=\"language-cpp\">    \/\/\u8fd4\u56de\u5f15\u7528\uff0c\u53ef\u4f5c\u4e3a\u5de6\u503c\u4fee\u6539\n    char&amp; operator[] (size_t pos);\n    char&amp; at (size_t pos);\n    char&amp; back();\n    char&amp; front();<\/code><\/pre>\n<h4>swap &amp; assign &amp; insert &amp; erase &amp; replace<\/h4>\n<pre><code class=\"language-cpp\">    void push_back (char c);\n    void pop_back();            \/\/\u5220\u9664\u6700\u540e\u4e00\u4e2a\u5b57\u7b26\n    void swap (string&amp; str);    \/\/\u4ea4\u6362\n    \/\/\u4ee5\u4e0b\u6709\u8f83\u591a\u91cd\u8f7d\u51fd\u6570\n    string&amp; append (const string&amp; str);             \/\/\n    string&amp; assign (const string&amp; str);             \/\/\u66ff\u6362\n    string&amp; insert (size_t pos, const string&amp; str); \/\/\u63d2\u5165\n    string&amp; erase (size_t pos = 0, size_t len = npos);\n    string&amp; replace (size_t pos\uff0c size_t len, const string&amp; str);<\/code><\/pre>\n<h4>copy &amp; find &amp; substr &amp; compare<\/h4>\n<pre><code class=\"language-cpp\">    const char* c_str() const noexcept;\n    const char* data() const noexcept;\n    size_t copy (char* s, size_t len, size_t pos = 0) const;\n\n    \/\/ \u4e00\u4e2a\u5b57\u7b26 \u641c\u7d22\u7b2c\u4e00\u6b21\u51fa\u73b0\u7684\u4f4d\u7f6efind \u548c \u641c\u7d22\u6700\u540e\u4e00\u6b21\u51fa\u73b0\u4f4d\u7f6e rfind\n    size_t find (const string&amp; str, size_t pos = 0) const noexcept; \/\/pos \u662f\u641c\u7d22\u8d77\u59cb\u4f4d\u7f6e\n    size_t find (const char* s, size_t pos = 0) const;\n    size_t rfind (const string&amp; str, size_t pos = npos) const noexcept; \n    size_t rfind (const char* s, size_t pos = npos) const;\n\n    \/\/ \u5b57\u7b26\u4e32\u4efb\u610f\u5b57\u7b26 \u641c\u7d22\u7b2c\u4e00\u6b21\u7684\u4f4d\u7f6e \u548c \u641c\u7d22\u6700\u540e\u4e00\u6b21\u51fa\u73b0\u4f4d\u7f6e\n    size_t find_first_of (const string&amp; str, size_t pos = 0) const noexcept;\n    size_t find_first_of (const char* s, size_t pos = 0) const;\n    size_t find_last_of (const string&amp; str, size_t pos = npos) const noexcept;\n    size_t find_last_of (const char* s, size_t pos = npos) const;\n    size_t find_first_not_of (const string&amp; str, size_t pos = 0) const noexcept;\n    size_t find_first_not_of (const char* s, size_t pos = 0) const;\n    size_t find_last_not_of (const string&amp; str, size_t pos = npos) const noexcept;\n    size_t find_last_not_of (const char* s, size_t pos = npos) const;\n\n    \/\/ \u5b50\u4e32\n    string substr (size_t pos = 0, size_t len = npos) const;\n\n    \/\/\u6bd4\u8f83\uff0c\u91cd\u8f7d\u8f83\u591a\uff0c\u4e5f\u53ef\u6bd4\u8f83\u5176\u4e2d\u4e00\u90e8\u5206\u5b57\u7b26\u4e32\n    int compare (const string&amp; str) const noexcept;<\/code><\/pre>\n<h3>3 cmath<\/h3>\n<h4>gamma\u51fd\u6570<\/h4>\n<pre><code class=\"language-cpp\">    double tgamma (     double x);\n    float tgamma (      float x);\n    long double tgamma (long double x);\n    double tgamma (T x);           \/\/ additional overloads for integral types<\/code><\/pre>\n<ol>\n<li>\u4e3e\u4e2a\u6817\u5b50<\/li>\n<\/ol>\n<pre><code class=\"language-cpp\">    \/* tgamma example *\/\n    #include &lt;stdio.h&gt;      \/* printf *\/\n    #include &lt;math.h&gt;       \/* tgamma *\/\n\n    int main ()\n    {\n      double param, result;\n      param = 0.5;\n      result = tgamma (param);\n      printf (\"tgamma(%f) = %f\\n\", param, result );\n      return 0;\n    }<\/code><\/pre>\n<ol>\n<li>\u8f93\u51fa<\/li>\n<\/ol>\n<pre><code class=\"language-cpp\">    tgamma (0.500000) = 1.772454<\/code><\/pre>\n<h4>\u53d6\u6574<\/h4>\n<pre><code class=\"language-cpp\">    \/\/ floor\u5411\u4e0b\u53d6\u6574\n    \/\/ ceil\u5411\u4e0a\u53d6\u6574\n    \/\/ round\u56db\u820d\u4e94\u5165\n    \/\/ \u8fd4\u56de\u7684\u662fdouble\uff0c\u4e0d\u662fint\n        cout&lt;&lt;floor(4.4)&lt;&lt;endl;\/\/4\n        cout&lt;&lt;floor(4.5)&lt;&lt;endl;\/\/4\n        cout&lt;&lt;ceil(4.4)&lt;&lt;endl;\/\/5\n        cout&lt;&lt;ceil(4.5)&lt;&lt;endl;\/\/5\n        cout&lt;&lt;round(4.4)&lt;&lt;endl;\/\/4\n        cout&lt;&lt;round(4.5)&lt;&lt;endl;\/\/5<\/code><\/pre>\n<h3>4 random<\/h3>\n<h4>\u6b63\u6001\u5206\u5e03<\/h4>\n<pre><code class=\"language-cpp\">    std::default_random_engine generator;                       \/\/\u5b9a\u4e49\u5f15\u64ce\n    std::normal_distribution&lt;double&gt; distribution(\u5747\u503c,\u6807\u51c6\u5dee);  \/\/\u5b9a\u4e49\u6b63\u6001\u5206\u5e03\n    double number = distribution(generator);                    \/\/\u4ea7\u751f\u5206\u5e03\u503c<\/code><\/pre>\n<ol>\n<li>\u4e3e\u4e2a\u6817\u5b50<\/li>\n<\/ol>\n<pre><code class=\"language-cpp\">    \/\/ normal_distribution\n    #include &lt;iostream&gt;\n    #include &lt;string&gt;\n    #include &lt;random&gt;\n\n    int main()\n    {\n      const int nrolls=10000;  \/\/ number of experiments\n      const int nstars=100;    \/\/ maximum number of stars to distribute\n\n      std::default_random_engine generator;\n      std::normal_distribution&lt;double&gt; distribution(5.0,2.0);\n\n      int p[10]={};\n\n      for (int i=0; i&lt;nrolls; ++i) {\n        double number = distribution(generator);\n        if ((number&gt;=0.0)&amp;&amp;(number&lt;10.0)) ++p[int(number)];\n      }\n\n      std::cout &lt;&lt; \"normal_distribution (5.0,2.0):\" &lt;&lt; std::endl;\n\n      for (int i=0; i&lt;10; ++i) {\n        std::cout &lt;&lt; i &lt;&lt; \"-\" &lt;&lt; (i+1) &lt;&lt; \": \";\n        std::cout &lt;&lt; std::string(p[i]*nstars\/nrolls,'*') &lt;&lt; std::endl;\n      }\n\n      return 0;\n    }<\/code><\/pre>\n<ol>\n<li>\u8f93\u51fa<\/li>\n<\/ol>\n<pre><code class=\"language-cpp\">    normal_distribution (5.0,2.0):\n    0-1: *\n    1-2: ****\n    2-3: *********\n    3-4: ***************\n    4-5: ******************\n    5-6: *******************\n    6-7: ***************\n    7-8: ********\n    8-9: ****\n    9-10: *<\/code><\/pre>\n<h3>5 algorithm<\/h3>\n<h4>sort &amp; reverse &amp; rotate<\/h4>\n<pre><code class=\"language-cpp\">    \/\/ \u6392\u5e8f\u539f\u7406\uff1a\u5feb\u901f\u6392\u5e8f\n    \/\/ \u6bd4\u8f83\u51fd\u6570comp\uff1a\u5c0f\u4e8e\u4e3a\u5347\u5e8f\u6392\u5217\uff0c\u5927\u4e8e\u4e3a\u964d\u5e8f\u6392\u5217\uff0c\u4e0d\u8f93\u5165\u6bd4\u8f83\u51fd\u6570\uff0c\u9ed8\u8ba4\u4e3a\u5347\u5e8f\u6392\u5217\n    void sort (RandomAccessIterator first, RandomAccessIterator last, Compare comp);\n    \/\/ e.g.\n    bool myfunction (int i,int j) \n    { \n        return (i&lt;j); \n    }\n\n    std::sort (myvector.begin(), myvector.end(), myfunction);\n\n    \/\/ \u6392\u5e8f\u539f\u7406\uff1amiddle\u4e4b\u524d\u7684\u5143\u7d20\uff0c\u4e3a\uff0c\u6309\u987a\u5e8f\uff0c\u5347\u5e8f\u6392\u5217\u6700\u5c0f\u7684n\u4e2a\u5143\u7d20\uff0c\u6216\u964d\u5e8f\u6392\u5217\u6700\u5927\u7684n\u4e2a\u5143\u7d20\uff1bmiddle\u4e4b\u540e\u6ca1\u6709\u7279\u5b9a\u987a\u5e8f\n    \/\/ \u6bd4\u8f83\u51fd\u6570comp\u4f5c\u7528\u540c\u4e0a\n    void partial_sort (RandomAccessIterator first, RandomAccessIterator middle, RandomAccessIterator last, Compare comp);\n\n    \/\/ \u5012\u5e8f\u6392\u5217\n    void reverse (BidirectionalIterator first, BidirectionalIterator last);\n\n    \/\/ \u65cb\u8f6c\u5bb9\u5668\uff0c\u4ee5middle\u4e3a\u7b2c\u4e00\u4e2a\u5143\u7d20\uff0c\u4e4b\u524d\u5143\u7d20\uff0c\u6709\u5e8f\u79fb\u52a8\u5230\u5c3e\u90e8\n    ForwardIterator rotate (ForwardIterator first, ForwardIterator middle, ForwardIterator last);\n    \/\/e.g.  1 2 3 4 5 6 7 8 9 ---&gt; 4 5 6 7 8 9 1 2 3<\/code><\/pre>\n<h4>min &amp; max &amp; min_element &amp; max_element<\/h4>\n<pre><code class=\"language-cpp\">    \/\/ \u6bd4\u8f83\u5927\u5c0f\n    \/\/ \u6bd4\u8f83\u51fd\u6570comp\uff1a\u8fd4\u56de\u503c\u4e3a a\u662f\u5426\u5c0f\u4e8eb\n    const T&amp; min (const T&amp; a, const T&amp; b, Compare comp);\n    \/\/ \u6bd4\u8f83\u51fd\u6570comp\uff1a\u8fd4\u56de\u503c\u4e3a a\u662f\u5426\u5c0f\u4e8eb\uff0c\u662f\u7684\uff0c\u8fd8\u662f\u201c\u662f\u5426\u5c0f\u4e8e\u201c\n    const T&amp; max (const T&amp; a, const T&amp; b, Compare comp);\n\n    \/\/ \u627e\u6700\u5927\/\u6700\u5c0f\u503c\u7684\u4f4d\u7f6e\uff0c\u8fd4\u56de\u7684\u662f\u6307\u5411\u8be5\u503c\u7684\u6307\u9488\n    ForwardIterator min_element (ForwardIterator first, ForwardIterator last, Compare comp);\n    ForwardIterator max_element (ForwardIterator first, ForwardIterator last, Compare comp);<\/code><\/pre>\n<h4>merge<\/h4>\n<pre><code class=\"language-cpp\">    \/\/ \u5408\u5e76\u4e24\u4e2a\u6392\u5e8f\u5e8f\u5217\n    \/\/ result \u662f\u5408\u5e76\u5230\u7684\u5bb9\u5668\u7684\u67d0\u4e2a\u4f4d\u7f6e\uff0c\u4e00\u822c\u662f\u8d77\u59cb\u4f4d\u7f6e\n    OutputIterator merge (InputIterator1 first1, InputIterator1 last1,\n                          InputIterator2 first2, InputIterator2 last2,\n                          OutputIterator result, Compare comp);<\/code><\/pre>\n<h4>copy<\/h4>\n<pre><code class=\"language-cpp\">    \/\/ \u590d\u5236first\u5230last\u8303\u56f4\u7684\u5185\u5bb9 \u5230 \u8d77\u59cb\u4f4d\u7f6eresult\n    OutputIterator copy (InputIterator first, InputIterator last, OutputIterator result);\n\n    \/\/ \u6709\u9009\u62e9\u5730\u590d\u5236\n    OutputIterator copy_if (InputIterator first, InputIterator last,\n                            OutputIterator result, UnaryPredicate pred);\n    \/\/e.g.\n    std::vector&lt;int&gt; foo = {25,15,5,-5,-15};\n    std::vector&lt;int&gt; bar (foo.size());\n    auto it = std::copy_if (foo.begin(), foo.end(), bar.begin(), [](int i){return !(i&lt;0);} );\n\n    \/\/ \u5012\u7740\u6765\n    BidirectionalIterator2 copy_backward (BidirectionalIterator1 first,\n                                          BidirectionalIterator1 last,\n                                          BidirectionalIterator2 result);<\/code><\/pre>\n<h4>move &amp; swap<\/h4>\n<pre><code class=\"language-cpp\">    \/\/ \u79fb\u52a8\u5230result\u540e\uff0c\u539f\u4f4d\u7f6e\u7684\u5143\u7d20\uff0c\u5904\u4e8e\u672a\u6307\u5b9a\u4f46\u6709\u6548\u72b6\u6001\n    OutputIterator move (InputIterator first, InputIterator last, OutputIterator result);\n    BidirectionalIterator2 move_backward (BidirectionalIterator1 first,\n                                          BidirectionalIterator1 last,\n                                          BidirectionalIterator2 result);\n\n    \/\/ C++11\u4e4b\u540e\uff0cswap\u4ea4\u6362\u57fa\u4e8emove\n    void swap (T&amp; a, T&amp; b);\n    void swap (T (&amp;a)[N], T (&amp;b)[N]);\n    \/\/\u4ea4\u6362\u4e00\u5b9a\u8303\u56f4\u7684\u503c\n    ForwardIterator2 swap_ranges (ForwardIterator1 first1, ForwardIterator1 last1, ForwardIterator2 first2);<\/code><\/pre>\n<h4>replace &amp; fill &amp; generate &amp; remove<\/h4>\n<pre><code class=\"language-cpp\">    \/\/ \u5355\u503c\u66ff\u6362\u5355\u503c\uff1a\u5c06\u8303\u56f4\u5185\u7684 old_value \u66ff\u6362\u6210 new_value\n    void replace (ForwardIterator first, ForwardIterator last, const T&amp; old_value, const T&amp; new_value);\n\n    \/\/ \u5355\u503c\u66ff\u6362\u6761\u4ef6\u503c\uff08\u591a\u503c\uff09\n    void replace_if (ForwardIterator first, ForwardIterator last, UnaryPredicate pred, const T&amp; new_value );\n\n    \/\/ \u8303\u56f4\u5185\u586b\u5145\u5355\u503c val\n    void fill (ForwardIterator first, ForwardIterator last, const T&amp; val);\n    OutputIterator fill_n (OutputIterator first, Size n, const T&amp; val); \/\/\u8fd4\u56de\u6700\u540e\u4e00\u4e2a\u586b\u5145\u503c\u7684\u4e0b\u4e00\u4e2a\u4f4d\u7f6e\uff08C++11\uff09\n\n    \/\/ \u8303\u56f4\u5185\u586b\u5145\u751f\u6210\u503c\n    void generate (ForwardIterator first, ForwardIterator last, Generator gen);\n    \/\/e.g.\n    \/\/ function generator:\n    int RandomNumber () { return (std::rand()%100); }\n    std::vector&lt;int&gt; myvector (8);\n    std::generate (myvector.begin(), myvector.end(), RandomNumber);\n\n    \/\/ \u79fb\u9664\u8303\u56f4\u5185\u7684\u503c\n    \/\/ \u5751\uff1a\u8fd9\u662f\u5047\u79fb\u9664\uff0c\u7b26\u5408\u79fb\u9664\u8981\u6c42\u7684\u503c\u88ab\u79fb\u52a8\u5230\u672b\u5c3e\uff0c\u6700\u540e\u8fd4\u56de\u7684\u4f4d\u7f6e\u6307\u5411 \u5c3e\u90e8 \u6240\u6709\u79fb\u9664\u5143\u7d20\u7684\u7b2c\u4e00\u4e2a\u5143\u7d20\u4f4d\u7f6e\n    ForwardIterator remove (ForwardIterator first, ForwardIterator last, const T&amp; val);<\/code><\/pre>\n<h4>find<\/h4>\n<pre><code class=\"language-cpp\">    \/\/ \u6d4b\u8bd5\u6240\u6709\u5143\u7d20\u6ee1\u8db3\u6761\u4ef6\n    bool all_of (InputIterator first, InputIterator last, UnaryPredicate pred);\n    \/\/ \u6d4b\u8bd5\u6709\u5143\u7d20\u6ee1\u8db3\u6761\u4ef6\n    bool any_of (InputIterator first, InputIterator last, UnaryPredicate pred);\n    \/\/ \u6d4b\u8bd5\u6240\u6709\u5143\u7d20\u4e0d\u6ee1\u8db3\u6761\u4ef6\n    bool none_of (InputIterator first, InputIterator last, UnaryPredicate pred);\n    \/\/ \u5bf9\u6bcf\u4e2a\u5143\u7d20\u6267\u884c\u4e00\u6b21\u51fd\u6570fn\n    Function for_each (InputIterator first, InputIterator last, Function fn);\n\n    \/\/ \u627e\u5230\u5143\u7d20\u7b2c\u4e00\u6b21\u51fa\u73b0\u7684\u4f4d\u7f6e\n    InputIterator find (InputIterator first, InputIterator last, const T&amp; val);\n    \/\/ \u6309\u6761\u4ef6\u7b2c\u4e00\u6b21\u51fa\u73b0\u7684\u4f4d\u7f6e\n    InputIterator find_if (InputIterator first, InputIterator last, UnaryPredicate pred);\n\n    \/\/ \u51fa\u73b0\u6b21\u6570\n    count (InputIterator first, InputIterator last, const T&amp; val);\n    count_if (InputIterator first, InputIterator last, UnaryPredicate pred);\n\n    \/\/ \u57281\u53f7\u8303\u56f4\u5185\uff0c\u7b2c\u4e00\u6b21\u51fa\u73b02\u53f7\u8303\u56f4\u5185\u5143\u7d20\u7684\u4f4d\u7f6e\uff0c  \u53ef\u81ea\u5b9a\u4e49pred \u5224\u65ad\u662f\u5426\u7b26\u5408\u5339\u914d\u60c5\u51b5\n    ForwardIterator1 search (ForwardIterator1 first1, ForwardIterator1 last1,\n                             ForwardIterator2 first2, ForwardIterator2 last2,\n                             BinaryPredicate pred);<\/code><\/pre>\n<h3>6 thread &amp; future<\/h3>\n<p>\uff08\u65b0\u5f00\u4e00\u4e2a\u535a\u5ba2\u5199\u591a\u7ebf\u7a0b&#8230;\uff09<\/p>\n","protected":false},"excerpt":{"rendered":"<p>&emsp;&emsp;\u8fd9\u4e00\u7cfb\u5217\u6587\u7ae0\u7684\u76ee\u7684\u662f\u5728\u5b66\u4e60\u4e86C++\u57fa\u7840\u540e\uff0c\u7ee7\u7eed\u8865\u5145\u4e00\u4e9bC++\u57fa\u7840\u548c\u8fdb\u9636\u7684\u77e5\u8bc6\u70b9\uff0c\u5305\u62ecC++11\u7684\u76f8\u5173\u5185\u5bb9\u3002 \u4ee5C++11\u6807\u51c6\u4e3a\u57fa\u7840\u3002 C++\u7f51\u7ad9\uff1ahttp:\/\/www.cplusplus.com\/reference\/ 1 ctime \/\/\u5305\u542b\u5934\u6587\u4ef6 #include &lt;ctime&gt; \/\/\u83b7\u53d6\u7cfb\u7edf\u65f6\u95f4 clock_t time = clock(); \/\/\u83b7\u53d6\u7cfb\u7edf\u65f6\u95f4\u5bf9\u5e94\u7684\u79d2\u6570 int sec = time\/CLOCKS_PER_SEC; 2 string string value transform #include &lt;string&gt; int std::stoi(const string&amp; str, size_t* idx = 0, int base = 10); int std::stol(const string&amp; str, size_t* idx = 0, int base = 10); int std::stoul(const string&amp; str, size_t* idx [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[6],"tags":[],"_links":{"self":[{"href":"http:\/\/47.103.123.166\/index.php?rest_route=\/wp\/v2\/posts\/169"}],"collection":[{"href":"http:\/\/47.103.123.166\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/47.103.123.166\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/47.103.123.166\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/47.103.123.166\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=169"}],"version-history":[{"count":1,"href":"http:\/\/47.103.123.166\/index.php?rest_route=\/wp\/v2\/posts\/169\/revisions"}],"predecessor-version":[{"id":170,"href":"http:\/\/47.103.123.166\/index.php?rest_route=\/wp\/v2\/posts\/169\/revisions\/170"}],"wp:attachment":[{"href":"http:\/\/47.103.123.166\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=169"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/47.103.123.166\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=169"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/47.103.123.166\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=169"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}