title: Execution time display in C++: cin/scanf/getchar_unlocked()
body: <p>I'm working on a project to show that <code>std::cin</code> is slower in taking input as compared to <code>scanf</code> which in turn will be slower than taking input via self written functions using <code>getchar/getchar_unlocked()</code> and so on.</p>
  
  <p>I want to record and print the execution time in each case but I don't know how to apply time and chrono etc header files.<br>
  I'll be reading a bulk of input values from stdin and want to display the execution time in each case.</p>
  
  <p>Please tell me how to deal with time in this with a short example.</p>