Determine if a string is collapsible: Difference between revisions

=={{header|Lua}}==

{{trans|C#}}

<lang lua>function collapse(s)

local ns = ""

local last = nil

for c in s:gmatch"." do

if last then

if last ~= c then

ns = ns .. c

end

last = c

else

ns = ns .. c

last = c

end

end

return ns

end

function test(s)

print("old: " .. s:len() .. " <<<" .. s .. ">>>")

local a = collapse(s)

print("new: " .. a:len() .. " <<<" .. a .. ">>>")

end

function main()

test("")

test("The better the 4-wheel drive, the further you'll be from help when ya get stuck!")

test("headmistressship")

test("\"If I were two-faced, would I be wearing this one?\" --- Abraham Lincoln ")

test("..1111111111111111111111111111111111111111111111111111111111111117777888")

test("I never give 'em hell, I just tell the truth, and they think it's hell. ")

test(" --- Harry S Truman ")

end

main()</lang>

{{out}}

<pre>old: 0 <<<>>>

new: 0 <<<>>>

old: 80 <<<The better the 4-wheel drive, the further you'll be from help when ya get stuck!>>>

new: 77 <<<The beter the 4-whel drive, the further you'l be from help when ya get stuck!>>>

old: 16 <<<headmistressship>>>

new: 14 <<<headmistreship>>>

old: 72 <<<"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln >>>

new: 70 <<<"If I were two-faced, would I be wearing this one?" - Abraham Lincoln >>>

old: 72 <<<..1111111111111111111111111111111111111111111111111111111111111117777888>>>

new: 4 <<<.178>>>

old: 72 <<<I never give 'em hell, I just tell the truth, and they think it's hell. >>>

new: 69 <<<I never give 'em hel, I just tel the truth, and they think it's hel. >>>

old: 72 <<< --- Harry S Truman >>>

new: 17 <<< - Hary S Truman >>></pre>