def sort_by_capital_letters(s)
s.split
.sort_by { |w| w[0].match?(/[A-Z]/) ? 1 : 0 }
.join(" ")
end
s = "ruby Programming Open source S-ource Ruby programming language"
s = sort_by_capital_letters(s)
print s
#
# run:
#
# ruby source programming language Programming Open S-ource Ruby
#