c++ - Does std::map::find performance depend on the key size? -


say have the following map definition:

std::map<string,storage>

where key string representation of storage class instance.
question is, though stated map::find complexity logarithmic in size, string size has influence on performance?

the reason have map enable fast access storage class instance. however, if string representation of storage classes long? there max string size if exceeded makes use of map redundant?

notes

my intuition tells me if the string representation of storage classes long comparing classes using operator== expensive well. no matter how long string is, i'm better of using map

yes, map has perform less-than comparison of keys. lexicographical comparison , linear wrt string size.

this not affect time complexity of find method, refers number of comparisons required. affects constant factor.

whether matters or not in application should determined empirically.


Comments

Post a Comment

Popular posts from this blog

user interface - How to replace the Python logo in a Tkinter-based Python GUI app? -

is there way change default logo, python logo , appears in window's task bar? notice have replaced default tk logo used appear in application window. i using windows 7 , python 2.6 , developing gui of tkinter. you can using winico tk extension package. winico package can used add system tray icons tk programs. the following sample shows 1 way change runtime application icon. note need provide .ico file suitable sizes of icons in on command line , need use pythonw. not change taskbar icon console when running python script. test extracted winico0.6 package python\tcl\winico0.6 folder package require winico work , ran code below using pythonw winico_test.py path\to\some\ico\file.ico . import sys tkinter import * def main(argv): root = tk() root.update() root.tk.call('package','require','winico') id = root.tk.call('winico','createfrom',argv[1]) root.tk.call('winico','setwindow',root,id...
Read more

android - Get AccessToken using signpost OAuth without opening a browser (Two legged Oauth) -

i using signpost oauth access data magento server. have read various tutorials on same , reach point open browser user can enter credentials. however, per requirement have automate part. hence, user should not browser page. have set-up done on server side ( magento ), hit url , returned call page. same through program in android. i have tried below, consumer = new commonshttpoauthconsumer(key, secret); provider = new commonshttpoauthprovider(oauth_init_url,access_token_url, authorize_url); try { provider.retrieverequesttoken(consumer, oauth.out_of_band); log.d("tokens" , consumer.gettoken() + " -- " + consumer.gettokensecret()); } and request tokens. dont know how bypass next step. tried directly accessing accesstoken (stupid of me) provider.retrieveaccesstoken(consumer, "mycallback://callback"); no luck, ends in oauth.signpost.exception.oauthnotauthorizedexception: authorization failed (server replied 401). ...
Read more

org.mockito.exceptions.misusing.InvalidUseOfMatchersException: mockito -

getting error org.mockito.exceptions.misusing.invaliduseofmatchersexception: invalid use of argument matchers! 1 matchers expected, 2 recorded. exception may occur if matchers combined raw values: //incorrect: somemethod(anyobject(), "raw string"); when using matchers, arguments have provided matchers. example: //correct: somemethod(anyobject(), eq("string matcher")); at when( getprogramservice .callservice(any(getprogramtype.class))) .thenreturn(jaxbresponse); please explain error , possible resolution the code posted looks fine; don't see problem it. code before or above causing exception. key here: invalid use of argument matchers! 1 matchers expected, 2 recorded. any , used above, doesn't return "special kind of null" or "special kind of getprogramtype"; don't exist. instead, returns null , side effect puts matcher on stack. whe...
Read more