正则表达式匹配从字符串中获取正确数字的简单逻辑

Question

Here I have a several different strings with salaries:

"U3 000 Per Month"
"U10 000 - U12 000 Per Month"
"U12 000 Per Month"
"U125 000 - U130 000 Per Month"
"U130 000 Per Month"

I'm trying to build a regex using the following logic:

Match the first 1,2 or 3 digits that come after first U letter only, then match zeros that come after a single space after first 1,2 or 3 digit group. The rest of the string doesn't matter. For example, we have few strings:

"U20 000 - U30 000 Per Month"
"U3 000 Per Month"
"U125 000 - U130 000 Per Month"

I want a regex to return

20000, 3000, 125000

Please help, I'm too exhausted of digging Regex documentation

Answer 1

You could try with (?<=^U)\\d{1,3}\\s0* .

regex = /(?<=^U)\d{1,3}\s0*/
p 'U20 000 - U30 000 Per Month'.scan(regex).first.sub(/\s/, '') # "20000"
p 'U3 000 Per Month'.scan(regex).first.sub(/\s/, '') # "3000"
p 'U125 000 - U130 000 Per Month'.scan(regex).first.sub(/\s/, '') # "125000"

I thought in only zeros after the \\s , so as you've added \\d{1,3} would fit better.