let compute_size_c_n_u c_n nbones_c_n_u iof_and_size_sol =
let iof_c_n j = Integer_var_map.find (Iof (c_n, j)) iof_and_size_sol in
let rec find j =
try iof_c_n j
with Not_found -> iof_c_n (j + 1) - 1
in
find (nbones_c_n_u + 1) - 1