Question

如何检查号码是否包含ruby中的其他号码？

示例：

number1 = 1321
number2 = 2

如何检查number1是否包含number2？

1321 contains 2 is true

Answer 1

你可以做这样的事情来返回真或假

number1.to_s.include?(number2.to_s)

Answer 2

这是字符串问题，而不是数字问题。数字不包含其他数字。您需要将两者都转换为字符串：

s1 = 1321.to_s # => "1321"
s2 = 2.to_s # => "2"

然后，只需使用[]：

s1[s2] # => "2"

这将返回找到的索引值，或nil：

s1["9"] # => nil

Answer 3

另一种方法是将数字转换为字符串，并使用String#include?检查主字符串中是否存在子字符串：

number1 = 1321
number2 = 2

sn1 = number1.to_s
# => "1321"
sn2 = number2.to_s
# => "2"

"#{sn1} contains #{sn2} is #{sn1.include?(sn2)}"
# => "1321 contains 2 is true"

错误案例：

number1 = 1321
number2 = 9

sn1 = number1.to_s
# => "1321"
sn2 = number2.to_s
# => "9"

"#{sn1} contains #{sn2} is #{sn1.include?(sn2)}"
# => "1321 contains 9 is false"

Answer 4

@meagar，可以被视为一个数字问题（某种程度上）：

def number_in_number?(outer, inner)
  test = 10**((inner < 2) ? 1 : Math.log10(inner).ceil.to_i)
  while outer >= inner
    return true if ((outer - inner) % test).zero?
    outer /= 10
  end
  false
end

number_in_number?(1321, 2)         #=> true 
number_in_number?(1321, 32)        #=> true 
number_in_number?(1321, 4)         #=> false
number_in_number?(1321, 1321)      #=> true 
number_in_number?(1321, 13211)     #=> false  
number_in_number?(543681321, 4368) #=> true 
number_in_number?(543681321, 4367) #=> false

支票号码包括红宝石中的其他号码

4 个答案: