Common commands in Linux

VI operations:

dd is used to delete one line

yy is used to copy one line

p is used to paste one line

GCC some useful operations:
-g is used to compile the program so that the debug program GDB can debug the execution.
-l is used to link the library, for example, -lm means to link "math" library.
-o used to name the execution file.

GDB some useful commands:
list : used to list the program in the source code.
break (line number) : used to set the break point.
run : run the program in GDB.
next(or n) : used to execute program step by step.
continue : execute the program until the end.
quit(or q) : exit GDB.
(press ENTER) : reexecute the last command.