루비(2)

#<<< 형변환 >>>
a = 123
a_double = 123.to_f
printf("%d\n", a)
printf("%.2f\n", a_double)

#<<< 문자열 >>>
str = "Welcome to hell korea"
p "#{str}"
p '#{str}'
puts str.include?("to")
puts str.include?("kim")