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#include <bits/stdc++.h>
using namespace std;
#define endl "\n"
#define mp make_pair
#define st first
#define nd second
#define pii pair<int, int>
#define vi vector<int>
#define pb push_back
#define _upgrade ios_base::sync_with_stdio(0), cout.setf(ios::fixed), cout.precision(10), cin.tie(0), cout.tie(0);
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define fwd(i, a, b) for (int i = (a); i < (b); ++i)
#define trav(a, x) for (auto &a : x)
#define all(c) (c).begin(), (c).end()
#define sz(X) (int)((X).size())
typedef long double ld;
typedef unsigned long long ull;
typedef long long ll;
#ifdef LOCAL
ostream &operator<<(ostream &out, string str) {
   for (char c : str)
      out << c;
   return out;
}
template <class L, class R> ostream &operator<<(ostream &out, pair<L, R> p) { return out << "(" << p.st << ", " << p.nd << ")"; }
template <class L, class R, class S> ostream &operator<<(ostream &out, tuple<L, R, S> p) {
   auto &[a, b, c] = p;
   return out << "(" << a << ", " << b << ", " << c << ")";
}
template <class T> auto operator<<(ostream &out, T a) -> decltype(a.begin(), out) {
   out << '{';
   for (auto it = a.begin(); it != a.end(); it = next(it))
      out << (it != a.begin() ? ", " : "") << *it;
   return out << '}';
}
void dump() { cerr << "\n"; }
template <class T, class... Ts> void dump(T a, Ts... x) {
   cerr << a << ", ";
   dump(x...);
}
#define debug(...) cerr << "[" #__VA_ARGS__ "]: ", dump(__VA_ARGS__)
#else
#define debug(...)
#endif

#define int long long
const int mod = 1e9 + 7;
typedef pair<int, char> pic;

namespace SOLVE {

#define NIEBIESKI 0
#define ZIELONY 1
#define CZERWONY 2

   const int MAXN = 2e5 + 99;
   int dp[MAXN][3];
   int tab[3][2];
   string S;
   int sum = 0;

   int get(char c) {
      if (c == 'N')
         return NIEBIESKI;
      if (c == 'Z')
         return ZIELONY;
      if (c == 'C')
         return CZERWONY;
      assert(false);
   }

   void remove(int i) {
      sum -= get(S[i]);
      tab[get(S[i])][i & 1]--;
   }
   void add(int i) {
      sum += get(S[i]);
      tab[get(S[i])][i & 1]++;
   }

   void init() {
      dp[0][0] = 1;
      for (int i = 1; i < MAXN; i++)
         rep(k, 3) {
            rep(l, 3) if (k != l) dp[i][k] += dp[i - 1][l];
            dp[i][k] %= mod;
         }
   }

   int get() {
      int n_cnt = tab[NIEBIESKI][0] + tab[NIEBIESKI][1];
      int res = mod;
      rep(k, 3) if (k != (sum % 3)) res += dp[n_cnt][k];
      int rest_cnt = sz(S) - n_cnt;
      // jezeli da się ułożyć wzorki (ZC)+Z
      if ((sz(S) & 1) && sz(S) > 1 && rest_cnt == tab[CZERWONY][1] + tab[ZIELONY][0])
         res--;
      // jezeli da się ułożyć wzorki (CZ)+C
      if ((sz(S) & 1) && sz(S) > 1 && rest_cnt == tab[CZERWONY][0] + tab[ZIELONY][1])
         res--;

      return res % mod;
   }

   vector<int> solve(string T, vector<pic> Q) {
      S = T;
      rep(i, sz(S)) add(i);
      vector<int> res = {get()};

      for (auto [i, c] : Q) {
         remove(i);
         S[i] = c;
         add(i);
         res.push_back(get());
      }
      return res;
   }
} // namespace SOLVE

int32_t main() {
   _upgrade;
   SOLVE::init();
   int n, q;
   cin >> n >> q;
   string S;
   cin >> S;
   vector<pic> Q(q);
   for (auto &[i, c] : Q) {
      cin >> i >> c;
      --i;
   }
   auto res = SOLVE::solve(S, Q);
   for (auto r : res)
      cout << r << endl;
}