C++

hash

std::map<string,int> prices; prices[‘aa’]=310; prices={‘aa’:310, ‘bb’:410}

stack

std::stack stk; stk.push(5); stk.pop(); //5

queue

std::queue q; q.push(5); ... 89 q.pop(); //5

from collections import deque stk=deque() stk.append(‘asadfas’) stk.pop()

• o(n) stk=[] stk.pop().rstk[-1]

collections import lifo deque() appendLeft(5) pop

stack

• automatically managed
• LIFO
• at compile time
• short term
• 8 MB : 8192 kb
• fast
• ulimit_a : show memory
• push / pop

heap

• need managed by yourself
• if we need to use more than 8 MB we need to use heap
• run time;
• dynamic
• long time
• new/delete
• slower

• pointer

• pmap ‘pidof _____’

  tail _n1

  grep_o ‘[0-9]*’

  awk ‘{print $ 0/(1024*1024)” [GiB]”}’

• tools
  • valgrind ./my_program
  • fsanitize = address
• echo %errorlevel%
• gflags /i print+Greeting.ext +sls

• cdb printGreeting.ext

• start with “/” is absolute path
• start with “folder/file…” is relative path
• ”/” is root
• ”~” is home folder
• ”.” is current folder

• ”..” is parent folder

• [a-c] is abc
• grep & ls.txt search inside file
• ”;” calls all command one after
• && same but if error strop next

• ”

  ” pipe

• htop
• struct like class that all members is public using for simple data

log level

1- debug 2- trace 3- info 4- critical 5- error 6- warning

• basic log
• defined

unit test google test md5sum

git

• git fixes #xx