String

Another interesting problem I met in statistic is: suppose we flip a coin which has probability 0.7 to be head again and again and two people choose two different sequences of length 3 (e.g. THH). The people whose sequence appears first wins. If you're allowed to choose first …

Performance

1. If there is some block of useless code, the compile is smart enough to ignore it and thus speed up the program.

2. Use the option -O2 to generate optimized code when you are ready to publish your code.

3. Define variables only when needed to avoid the overhead of creating …

Lambda Function

Check [here[(https://github.com/dclong/cearn/tree/master/lambda) for illustrative examples for the following discussions.

1. When capture variables, you can define new variables in the [] of a lambda expression. For example, if a lambda function need the sum of two double variable x and y, you …

The kernel of Linux is usually very stable, but the existing free desktop environments are craps. Amongs these desktop environments I tried (Gnome, Xfce, LXDE and so on), none is even close to the desktop environments in Windows and Mac. I do not require desktop environments in Linux to be …

1. {} is more powerful than () and thus is preferred over (). You should use always use {} except for a few cases where () is necessary. For example, if you want to create a vector of length 1000, you have to use

   vector<int>(1000);
   

instead of

    vector<int> {1000};

which create a vector …