First non repeating character position in a string
# First non repeating character position in a string
def first_non_repeating_letter(str)
strL = str.downcase
strL.each_char.with_index do |v, i|
if strL.index(v) == strL.rindex(v)
return i
end
end
-1
end
print "First non repeating character position = ",
first_non_repeating_letter("abcdcba"); # 3