Since qiita often uses Markdown, I will leave the qiita article below for notes. Markdown Writing Cheat Sheet
Convention over Configuration
Details of Configuration over Configuration
shebang
This time, shebang was explained.
What is a shebang? shebang is the first line of a UNIX script that starts with #! And specifies the interpreter to start and load the script.
If the path is set, it can be converted into a command, and the program can be handled conveniently.
With this setting, programs under ~ / bin can be easily used if you have execute permission! !!
Use the chmod command for execution privileges. You can check the contents with man chmod </ strong>.
Ruby handles if-else statements as follows
if expression[then]
formula...
[elsif expression[then]
formula... ]
...
[else
formula... ]
end
Class review 1
--How to handle if-else statements in ruby
p year = ARGV[0].to_i
# .to_i is a method to convert to int type
if year % 4 == 0
p true
end
Class review 2
--How to handle arrays and loop statements in ruby
[2004, 1999].each do |year|
# []Array (same as python list)
#Extract elements in order with each method
p year
if year%4 == 0
p true
else
p false
end
end
Class review 3
--More detailed loop statement
[1900,2004,1999].each do |year|
p year
#The first if statement
if year % 100 ==0
p false
next #next is the same as the python continue statement
end
#Second if statement
if year % 4 == 0
p true
else
p false
end
end
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