use vstd::prelude::*; fn main() {} verus! { pub struct Solution; impl Solution { pub open spec fn common_divisor(cnt: Seq, d: int) -> bool recommends cnt.len() == 30, { &&& 1 <= d &&& forall|b: int| 0 <= b < 30 ==> #[trigger] ((cnt[b] as int) % d) == 0 } pub open spec fn valid_answer(n: int, cnt: Seq, ans: Seq) -> bool recommends cnt.len() == 30, n >= 1, { &&& forall|idx: int| 0 <= idx < ans.len() ==> 1 <= ans[idx] as int <= n && Self::common_divisor(cnt, ans[idx] as int) &&& forall|d: int| 1 <= d <= n && Self::common_divisor(cnt, d) ==> exists|idx: int| 0 <= idx < ans.len() && ans[idx] as int == d &&& forall|i: int, j: int| 0 <= i < j < ans.len() ==> #[trigger] ans[i] < #[trigger] ans[j] } pub fn valid_k_values(n: usize, cnt: Vec) -> (ans: Vec) requires 1 <= n <= 200_000, cnt.len() == 30, forall|i: int| 0 <= i < 30 ==> 0 <= #[trigger] cnt[i] <= n, ensures Self::valid_answer(n as int, cnt@, ans@), { let mut ans: Vec = Vec::new(); let mut k: usize = 1; while k <= n { let k_i32: i32 = k as i32; let mut b: usize = 0; let mut bad_idx: i32 = -1; while b < 30 { if bad_idx == -1 && cnt[b] % k_i32 != 0 { bad_idx = b as i32; } b = b + 1; } if bad_idx == -1 { ans.push(k as i32); } k = k + 1; } ans } } }