concatDeuxListes (x:xs) ys = concatDeuxListes [x] (concatDeuxListes xs ys)
concatDeuxListes (x:xs) ys = concatDeuxListes [x] (concatDeuxListes xs ys)
concatDeuxListes (x:xs) ys = concatDeuxListes [x] (concatDeuxListes xs ys)