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#include <iostream>
#include <chrono>
#include <cstdlib>
#include <ctime>
 
class Duration {
  std::chrono::high_resolution_clock::time_point beg, duration;
public:
  Duration() {
    beg = std::chrono::high_resolution_clock::now();
  }
  ~Duration() {
    duration = std::chrono::high_resolution_clock::now();
    std::cout << std::chrono::duration_cast<std::chrono::milliseconds>(duration - beg).count() << "ms" << std::endl;
  }
};
 
const int N = 10000000;
 
int rnd[N];
 
void func1()
{
  return;
}
 
void func2()
{
  return;
}
 
void func3()
{
  return;
}
 
void func4()
{
  return;
}
 
int main()
{
  void (*func[])() = { func1, func2, func3, func4 }; // Avoid std::function costs
 
  {
    std::cout << "The same function call" << std::endl;
    Duration d;
 
    for (int i = 0; i < N; i++)
      func[0]();
  }
 
  {
    std::srand(std::time(0));
    for (int i = 0; i < N; i++)
      rnd[i] = std::rand() % 4; // Avoid std::rand() costs
    std::cout << "Random function call" << std::endl;
    Duration d;
 
    for (int i = 0; i < N; i++)
      func[rnd[i]]();
  }
}
 

In file included from /usr/include/c++/4.8/chrono:35:0,
                 from prog.cpp:2:
/usr/include/c++/4.8/bits/c++0x_warning.h:32:2: error: #error This file requires compiler and library support for the ISO C++ 2011 standard. This support is currently experimental, and must be enabled with the -std=c++11 or -std=gnu++11 compiler options.
 #error This file requires compiler and library support for the \
  ^
prog.cpp:7:3: error: ‘chrono’ in namespace ‘std’ does not name a type
   std::chrono::high_resolution_clock::time_point beg, duration;
   ^
prog.cpp: In constructor ‘Duration::Duration()’:
prog.cpp:10:5: error: ‘beg’ was not declared in this scope
     beg = std::chrono::high_resolution_clock::now();
     ^
prog.cpp:10:16: error: ‘std::chrono’ has not been declared
     beg = std::chrono::high_resolution_clock::now();
                ^
prog.cpp: In destructor ‘Duration::~Duration()’:
prog.cpp:13:5: error: ‘duration’ was not declared in this scope
     duration = std::chrono::high_resolution_clock::now();
     ^
prog.cpp:13:21: error: ‘std::chrono’ has not been declared
     duration = std::chrono::high_resolution_clock::now();
                     ^
prog.cpp:14:23: error: ‘std::chrono’ has not been declared
     std::cout << std::chrono::duration_cast<std::chrono::milliseconds>(duration - beg).count() << "ms" << std::endl;
                       ^
prog.cpp:14:50: error: ‘std::chrono’ has not been declared
     std::cout << std::chrono::duration_cast<std::chrono::milliseconds>(duration - beg).count() << "ms" << std::endl;
                                                  ^
prog.cpp:14:83: error: ‘beg’ was not declared in this scope
     std::cout << std::chrono::duration_cast<std::chrono::milliseconds>(duration - beg).count() << "ms" << std::endl;
                                                                                   ^

Standard output is empty