string s = "what,is,the;meaning,of:life."
--string s = "we,are;not,in,kansas;any,more."
integer i = 0

function getchar()
    i += 1
    return s[i]
end function

function wrod(integer rev)
    integer ch = getchar(), nch
--  integer ch = getc(0), nch
    if not find(ch," .,:;!?") then
        if rev then
            nch = wrod(rev)
        end if
        puts(1,ch)
        if not rev then
            nch = wrod(rev)
        end if
        ch = nch
    end if
    return ch
end function

--puts(1,"Enter words separated by a single punctuation mark (i.e. !?,.;:) and ending with .\n")
integer rev = 0
while 1 do
    integer ch = wrod(rev)
    puts(1,ch)
    if ch='.' then exit end if
    rev = 1-rev
end while