re = /.*\/videos\/(.*?mp4).*?(?<= )(\d+)/m
str = 'https://videos-a.jwpsrv.com/content/conversions/7kHOkkQa/videos/JajSfbVN-32313922.mp4.m3u8?hdnts=exp=1592315891~acl=*/JajSfbVN-32313922.mp4.m3u8~hmac=d3ca7bd5b233a531cfe242d17d2ea0c0167b41b90fff6459e433700ffc969d69 19
https://videos-a.jwpsrv.com/content/conversions/7kHOkkQa/videos/Qs3xZqcv-32313922.mp4.m3u8?hdnts=exp=1592315940~acl=*/Qs3xZqcv-32313922.mp4.m3u8~hmac=c30e2082bf748a6b4d1621c1d33a95319baa61798775e9da8856041951cf5233 20'
subst = '$1 $2'
result = str.gsub(re, subst)
# Print the result of the substitution
puts result
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html