re = /(?<=\d)(?=[^\d\s])|(?<=[^\d\s])(?=\d)/m
str = '0ABCD TECHNOLOGIES SERVICES
ABCD0 TECHNOLOGIES SERVICES
ABCD 0TECHNOLOGIES SERVICES
ABCD TECHNOLOGIES0 SERVICES
ABCD TECHNOLOGIES 0SERVICES
ABCD TECHNOLOGIES SERVICES0
'
subst = ' '
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