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  1. #include <iostream>
  2. #include <vector>
  3.  
  4. class X
  5. {
  6.     int i_;
  7.     int* p_;
  8.  
  9. public:
  10.     struct special
  11.     {
  12.         unsigned c;
  13.         unsigned dt;
  14.         unsigned cc;
  15.         unsigned ca;
  16.         unsigned mc;
  17.         unsigned ma;
  18.     };
  19.     static special sp;
  20.  
  21.     X(int i, int* p)
  22.         : i_(i)
  23.         , p_(p)
  24.     {
  25. //         std::cout << "X(int i, int* p)\n";
  26.         sp.c++;
  27.     }
  28.  
  29.     ~X()
  30.     {
  31. //         std::cout << "~X()\n";
  32.         sp.dt++;
  33.     }
  34.  
  35.     X(const X& x)
  36.         : i_(x.i_)
  37.         , p_(x.p_)
  38.     {
  39. //         std::cout << "X(const X& x)\n";
  40.         sp.cc++;
  41.     }
  42.  
  43.     X& operator=(const X& x)
  44.     {
  45.  
  46.         i_ = x.i_;
  47.         p_ = x.p_;
  48. //         std::cout << "X& operator=(const X& x)\n";
  49.         sp.ca++;
  50.         return *this;
  51.     }
  52.  
  53.     X(X&& x) noexcept
  54.         : i_(x.i_)
  55.         , p_(x.p_)
  56.     {
  57. //         std::cout << "X(X&& x)\n";
  58.         sp.mc++;
  59.     }
  60.  
  61.     X& operator=(X&& x) noexcept
  62.     {
  63.  
  64.         i_ = x.i_;
  65.         p_ = x.p_;
  66. //         std::cout << "X& operator=(X&& x)\n";
  67.         sp.ma++;
  68.         return *this;
  69.     }
  70.  
  71. };
  72.  
  73. std::ostream&
  74. operator<<(std::ostream& os, X::special const& sp)
  75. {
  76.     os << sp.c << '\n';
  77.     os << sp.dt << '\n';
  78.     os << sp.cc << '\n';
  79.     os << sp.ca << '\n';
  80.     os << sp.mc << '\n';
  81.     os << sp.ma << '\n';
  82.     return os;
  83. }
  84.  
  85. X::special X::sp{};
  86.  
  87. int
  88. main()
  89. {
  90.     {
  91.         std::vector<X> v;
  92.         v.reserve(4);
  93.         v.push_back(X(0,0));
  94.         v.push_back(X(0,0));
  95.         v.push_back(X(0,0));
  96.         X x{0,0};
  97.         std::cout << "--insert lvalue no reallocation--\n";
  98.         X::sp = {};
  99.         v.insert(v.begin(), x);
  100.         std::cout << X::sp;
  101.         std::cout << "----\n";
  102.     }
  103.     {
  104.         std::vector<X> v;
  105.         v.reserve(4);
  106.         v.push_back(X(0,0));
  107.         v.push_back(X(0,0));
  108.         v.push_back(X(0,0));
  109.         X x{0,0};
  110.         std::cout << "--emplace lvalue no reallocation--\n";
  111.         X::sp = {};
  112.         v.emplace(v.begin(), x);
  113.         std::cout << X::sp;
  114.         std::cout << "----\n";
  115.     }
  116.     {
  117.         std::vector<X> v;
  118.         v.reserve(4);
  119.         v.push_back(X(0,0));
  120.         v.push_back(X(0,0));
  121.         v.push_back(X(0,0));
  122.         X x{0,0};
  123.         std::cout << "--insert xvalue no reallocation--\n";
  124.         X::sp = {};
  125.         v.insert(v.begin(), std::move(x));
  126.         std::cout << X::sp;
  127.         std::cout << "----\n";
  128.     }
  129.     {
  130.         std::vector<X> v;
  131.         v.reserve(4);
  132.         v.push_back(X(0,0));
  133.         v.push_back(X(0,0));
  134.         v.push_back(X(0,0));
  135.         X x{0,0};
  136.         std::cout << "--emplace xvalue no reallocation--\n";
  137.         X::sp = {};
  138.         v.emplace(v.begin(), std::move(x));
  139.         std::cout << X::sp;
  140.         std::cout << "----\n";
  141.     }
  142.     {
  143.         std::vector<X> v;
  144.         v.reserve(4);
  145.         v.push_back(X(0,0));
  146.         v.push_back(X(0,0));
  147.         v.push_back(X(0,0));
  148.         std::cout << "--insert rvalue no reallocation--\n";
  149.         X::sp = {};
  150.         v.insert(v.begin(), X{0,0});
  151.         std::cout << X::sp;
  152.         std::cout << "----\n";
  153.     }
  154.     {
  155.         std::vector<X> v;
  156.         v.reserve(4);
  157.         v.push_back(X(0,0));
  158.         v.push_back(X(0,0));
  159.         v.push_back(X(0,0));
  160.         std::cout << "--emplace rvalue no reallocation--\n";
  161.         X::sp = {};
  162.         v.emplace(v.begin(), X{0,0});
  163.         std::cout << X::sp;
  164.         std::cout << "----\n";
  165.     }
  166.     {
  167.         std::vector<X> v;
  168.         v.reserve(3);
  169.         v.push_back(X(0,0));
  170.         v.push_back(X(0,0));
  171.         v.push_back(X(0,0));
  172.         X x{0,0};
  173.         std::cout << "--insert lvalue reallocation--\n";
  174.         X::sp = {};
  175.         v.insert(v.begin(), x);
  176.         std::cout << X::sp;
  177.         std::cout << "----\n";
  178.     }
  179.     {
  180.         std::vector<X> v;
  181.         v.reserve(3);
  182.         v.push_back(X(0,0));
  183.         v.push_back(X(0,0));
  184.         v.push_back(X(0,0));
  185.         X x{0,0};
  186.         std::cout << "--emplace lvalue reallocation--\n";
  187.         X::sp = {};
  188.         v.emplace(v.begin(), x);
  189.         std::cout << X::sp;
  190.         std::cout << "----\n";
  191.     }
  192.     {
  193.         std::vector<X> v;
  194.         v.reserve(3);
  195.         v.push_back(X(0,0));
  196.         v.push_back(X(0,0));
  197.         v.push_back(X(0,0));
  198.         X x{0,0};
  199.         std::cout << "--insert xvalue reallocation--\n";
  200.         X::sp = {};
  201.         v.insert(v.begin(), std::move(x));
  202.         std::cout << X::sp;
  203.         std::cout << "----\n";
  204.     }
  205.     {
  206.         std::vector<X> v;
  207.         v.reserve(3);
  208.         v.push_back(X(0,0));
  209.         v.push_back(X(0,0));
  210.         v.push_back(X(0,0));
  211.         X x{0,0};
  212.         std::cout << "--emplace xvalue reallocation--\n";
  213.         X::sp = {};
  214.         v.emplace(v.begin(), std::move(x));
  215.         std::cout << X::sp;
  216.         std::cout << "----\n";
  217.     }
  218.     {
  219.         std::vector<X> v;
  220.         v.reserve(3);
  221.         v.push_back(X(0,0));
  222.         v.push_back(X(0,0));
  223.         v.push_back(X(0,0));
  224.         std::cout << "--insert rvalue reallocation--\n";
  225.         X::sp = {};
  226.         v.insert(v.begin(), X{0,0});
  227.         std::cout << X::sp;
  228.         std::cout << "----\n";
  229.     }
  230.     {
  231.         std::vector<X> v;
  232.         v.reserve(3);
  233.         v.push_back(X(0,0));
  234.         v.push_back(X(0,0));
  235.         v.push_back(X(0,0));
  236.         std::cout << "--emplace rvalue reallocation--\n";
  237.         X::sp = {};
  238.         v.emplace(v.begin(), X{0,0});
  239.         std::cout << X::sp;
  240.         std::cout << "----\n";
  241.     }
  242.  
  243.     {
  244.         std::vector<X> v;
  245.         v.reserve(4);
  246.         v.push_back(X(0,0));
  247.         v.push_back(X(0,0));
  248.         v.push_back(X(0,0));
  249.         X x{0,0};
  250.         std::cout << "--push_back lvalue no reallocation--\n";
  251.         X::sp = {};
  252.         v.push_back(x);
  253.         std::cout << X::sp;
  254.         std::cout << "----\n";
  255.     }
  256.     {
  257.         std::vector<X> v;
  258.         v.reserve(4);
  259.         v.push_back(X(0,0));
  260.         v.push_back(X(0,0));
  261.         v.push_back(X(0,0));
  262.         X x{0,0};
  263.         std::cout << "--emplace_back lvalue no reallocation--\n";
  264.         X::sp = {};
  265.         v.emplace_back(x);
  266.         std::cout << X::sp;
  267.         std::cout << "----\n";
  268.     }
  269.     {
  270.         std::vector<X> v;
  271.         v.reserve(4);
  272.         v.push_back(X(0,0));
  273.         v.push_back(X(0,0));
  274.         v.push_back(X(0,0));
  275.         X x{0,0};
  276.         std::cout << "--push_back xvalue no reallocation--\n";
  277.         X::sp = {};
  278.         v.push_back(std::move(x));
  279.         std::cout << X::sp;
  280.         std::cout << "----\n";
  281.     }
  282.     {
  283.         std::vector<X> v;
  284.         v.reserve(4);
  285.         v.push_back(X(0,0));
  286.         v.push_back(X(0,0));
  287.         v.push_back(X(0,0));
  288.         X x{0,0};
  289.         std::cout << "--emplace_back xvalue no reallocation--\n";
  290.         X::sp = {};
  291.         v.emplace_back(std::move(x));
  292.         std::cout << X::sp;
  293.         std::cout << "----\n";
  294.     }
  295.     {
  296.         std::vector<X> v;
  297.         v.reserve(4);
  298.         v.push_back(X(0,0));
  299.         v.push_back(X(0,0));
  300.         v.push_back(X(0,0));
  301.         std::cout << "--push_back rvalue no reallocation--\n";
  302.         X::sp = {};
  303.         v.push_back(X{0,0});
  304.         std::cout << X::sp;
  305.         std::cout << "----\n";
  306.     }
  307.     {
  308.         std::vector<X> v;
  309.         v.reserve(4);
  310.         v.push_back(X(0,0));
  311.         v.push_back(X(0,0));
  312.         v.push_back(X(0,0));
  313.         std::cout << "--emplace_back rvalue no reallocation--\n";
  314.         X::sp = {};
  315.         v.emplace_back(X{0,0});
  316.         std::cout << X::sp;
  317.         std::cout << "----\n";
  318.     }
  319.     {
  320.         std::vector<X> v;
  321.         v.reserve(3);
  322.         v.push_back(X(0,0));
  323.         v.push_back(X(0,0));
  324.         v.push_back(X(0,0));
  325.         X x{0,0};
  326.         std::cout << "--push_back lvalue reallocation--\n";
  327.         X::sp = {};
  328.         v.push_back(x);
  329.         std::cout << X::sp;
  330.         std::cout << "----\n";
  331.     }
  332.     {
  333.         std::vector<X> v;
  334.         v.reserve(3);
  335.         v.push_back(X(0,0));
  336.         v.push_back(X(0,0));
  337.         v.push_back(X(0,0));
  338.         X x{0,0};
  339.         std::cout << "--emplace_back lvalue reallocation--\n";
  340.         X::sp = {};
  341.         v.emplace_back(x);
  342.         std::cout << X::sp;
  343.         std::cout << "----\n";
  344.     }
  345.     {
  346.         std::vector<X> v;
  347.         v.reserve(3);
  348.         v.push_back(X(0,0));
  349.         v.push_back(X(0,0));
  350.         v.push_back(X(0,0));
  351.         X x{0,0};
  352.         std::cout << "--push_back xvalue reallocation--\n";
  353.         X::sp = {};
  354.         v.push_back(std::move(x));
  355.         std::cout << X::sp;
  356.         std::cout << "----\n";
  357.     }
  358.     {
  359.         std::vector<X> v;
  360.         v.reserve(3);
  361.         v.push_back(X(0,0));
  362.         v.push_back(X(0,0));
  363.         v.push_back(X(0,0));
  364.         X x{0,0};
  365.         std::cout << "--emplace_back xvalue reallocation--\n";
  366.         X::sp = {};
  367.         v.emplace_back(std::move(x));
  368.         std::cout << X::sp;
  369.         std::cout << "----\n";
  370.     }
  371.     {
  372.         std::vector<X> v;
  373.         v.reserve(3);
  374.         v.push_back(X(0,0));
  375.         v.push_back(X(0,0));
  376.         v.push_back(X(0,0));
  377.         std::cout << "--push_back rvalue reallocation--\n";
  378.         X::sp = {};
  379.         v.push_back(X{0,0});
  380.         std::cout << X::sp;
  381.         std::cout << "----\n";
  382.     }
  383.     {
  384.         std::vector<X> v;
  385.         v.reserve(3);
  386.         v.push_back(X(0,0));
  387.         v.push_back(X(0,0));
  388.         v.push_back(X(0,0));
  389.         std::cout << "--emplace_back rvalue reallocation--\n";
  390.         X::sp = {};
  391.         v.emplace_back(X{0,0});
  392.         std::cout << X::sp;
  393.         std::cout << "----\n";
  394.     }
  395. }
  396.  
Success #stdin #stdout 0s 3444KB
comments (?)
stdin
copy 
Standard input is empty
stdout
copy 
--insert lvalue no reallocation--
0
2
1
0
2
3
----
--emplace lvalue no reallocation--
0
1
1
0
1
3
----
--insert xvalue no reallocation--
0
1
0
0
2
3
----
--emplace xvalue no reallocation--
0
1
0
0
2
3
----
--insert rvalue no reallocation--
1
2
0
0
2
3
----
--emplace rvalue no reallocation--
1
2
0
0
2
3
----
--insert lvalue reallocation--
0
3
1
0
3
0
----
--emplace lvalue reallocation--
0
3
1
0
3
0
----
--insert xvalue reallocation--
0
3
0
0
4
0
----
--emplace xvalue reallocation--
0
3
0
0
4
0
----
--insert rvalue reallocation--
1
4
0
0
4
0
----
--emplace rvalue reallocation--
1
4
0
0
4
0
----
--push_back lvalue no reallocation--
0
0
1
0
0
0
----
--emplace_back lvalue no reallocation--
0
0
1
0
0
0
----
--push_back xvalue no reallocation--
0
0
0
0
1
0
----
--emplace_back xvalue no reallocation--
0
0
0
0
1
0
----
--push_back rvalue no reallocation--
1
1
0
0
1
0
----
--emplace_back rvalue no reallocation--
1
1
0
0
1
0
----
--push_back lvalue reallocation--
0
3
1
0
3
0
----
--emplace_back lvalue reallocation--
0
3
1
0
3
0
----
--push_back xvalue reallocation--
0
3
0
0
4
0
----
--emplace_back xvalue reallocation--
0
3
0
0
4
0
----
--push_back rvalue reallocation--
1
4
0
0
4
0
----
--emplace_back rvalue reallocation--
1
4
0
0
4
0
----
https://ideone.com/imAMnU
language:
C++14 (gcc 8.3)
created:
10 years ago
visibility:
public

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