Haskell concat Int -

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i having trouble following exercise:

i must make function named adddigit, takes 2 int's, second 1 being between 0 , 9, , return int first int followed second one.

example:

input: adddigit (-123) 4

output: -1234

what have tried following :

adddigit :: int -> int -> int adddigit x y = x ++ y

i doesn't work because ++ keyword works strings, chars , lists (i think), , supposed solved in simple way without changing int's strings or sort of other variables, have no clue @ on how it.

you trying solve problem graphically (thinking of integers strings), want treat numerical problem. positive values, appending digit accomplished following function.

adddigitpositive b = 10 * + b

this unfortunately not work if a < 0. under circumstances have subtract b. can incorporate functionality function guards.

adddigit b | < 0     = * 10 - b              | otherwise = * 10 + b

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