#include <algorithm>
#include <array>
#include <cstdint>
#include <iostream>
#include <vector>

using namespace std;

constexpr int N = 301, mod = 998244353;

void add(int& a, int b) { a += b, a -= a >= mod? mod: 0; }

int dp[N][N][N];

int main() {
  cin.tie(0)->sync_with_stdio(0);
  int n, m; cin >> n >> m;
  string s; cin >> s;
  vector<int> a(m);
  for (auto& a: a) cin >> a, --a;
  reverse(a.begin(), a.end());
  dp[0][0][0] = 1;
  for (int i = 0, d = 0; i < n + m; d += s[i++] == '-') {
    if (s[i] == '+') {
      for (int l = 0; l <= d; ++l)
      for (int c = i - d + 1; c-- > d; )
      if (int x = n - (l == m? 0: a[l] + 1) - l - i + d + c; 1)
      for (int t = 0; t <= c - l; ++t) {
        add(dp[l][c + 1][t + 1], dp[l][c][t]);
        dp[l][c][t] = dp[l][c][t] * uint64_t(x) % mod;
      } else if (x >= 0) for (int t = 0; t <= c - l; ++t) add(dp[l][c + 1][t + 1], dp[l][c][t]), dp[l][c][t] = 0;
    } else {
      for (int l = d + 1; l--; ) {
        for (int j = 1, A = 1; j <= d + 1 - l; A = A * (d + 1ull - l - j++) % mod) {
          uint64_t tmp = 0;
          for (int t = 1; t <= d + 1 - l; ++t) tmp += (uint64_t)t * dp[l][d + 1][t];
          dp[l + j][d + 1][0] = (dp[l + j][d + 1][0] + tmp % mod * A) % mod;
        }
        for (int t = 1; t <= d + 1 - l; ++t) add(dp[l][d + 1][0], dp[l][d + 1][t]), dp[l][d + 1][t] = 0;
      }
    }
  }
  cout << dp[m][m][0] << '\n';
}