#include #include #include #include #include #include using std::cin; using std::cout; const char endl = '\n'; const int N = 105; const int mod = 998244353; int n, a[N], p[N], f[N][N][N]; std::vector> nums; int solve(int l, int r, int x) { if (x == 0) return 1; if (l == r) return 1; if (f[l][r][x] != -1) return f[l][r][x]; int pos = std::find(p + l, p + r + 1, x) - p; if (pos > r) { return f[l][r][x] = solve(l, r, x - 1); } int res = 0; for (int i = pos; i <= r; i++) { if (p[i] <= x) { res = (res + static_cast(solve(l, i, x - 1)) * solve(i + 1, r, x) % mod) % mod; } } return f[l][r][x] = res; } int main() { std::ios::sync_with_stdio(false); cin.tie(nullptr); cin >> n; for (int i = 1; i <= n; i++) { cin >> a[i]; nums.emplace_back(a[i], i); } std::sort(nums.begin(), nums.end()); nums.erase(std::unique(nums.begin(), nums.end()), nums.end()); for (int i = 1; i <= n; i++) { p[i] = std::distance(nums.begin(), std::lower_bound(nums.begin(), nums.end(), std::pair{a[i], i})); } memset(f, 0xff, sizeof(f)); cout << solve(1, n, n) << endl; return 0; }