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#pragma GCC optimize("O3")
#include <bits/stdc++.h>
// #include <ext/pb_ds/assoc_container.hpp>
// using namespace __gnu_pbds;
// gp_hash_table<int, int> mapka;

using namespace std;
#define PB push_back
#define MP make_pair
#define LL long long
#define int LL
#define FOR(i,a,b) for(int i = (a); i <= (b); i++)
#define RE(i,n) FOR(i,1,n)
#define REP(i,n) FOR(i,0,(int)(n)-1)
#define R(i,n) REP(i,n)
#define VI vector<int>
#define PII pair<int,int>
#define LD long double
#define FI first
#define SE second
#define st FI
#define nd SE
#define ALL(x) (x).begin(), (x).end()
#define SZ(x) ((int)(x).size())

template<class C> void mini(C &a4, C b4) { a4 = min(a4, b4); }
template<class C> void maxi(C &a4, C b4) { a4 = max(a4, b4); }

template<class TH> void _dbg(const char *sdbg, TH h){ cerr<<sdbg<<'='<<h<<endl; }
template<class TH, class... TA> void _dbg(const char *sdbg, TH h, TA... a) {
  while(*sdbg!=',')cerr<<*sdbg++;
  cerr<<'='<<h<<','; _dbg(sdbg+1, a...);
}

template<class T> ostream &operator<<(ostream& os, vector<T> V) {
  os << "["; for (auto vv : V) os << vv << ","; return os << "]";
}
template<class L, class R> ostream &operator<<(ostream &os, pair<L,R> P) {
  return os << "(" << P.st << "," << P.nd << ")";
}

#ifdef LOCAL
#define debug(...) _dbg(#__VA_ARGS__, __VA_ARGS__)
#else
#define debug(...) (__VA_ARGS__)
#define cerr if(0)cout
#endif

int sum = 0;
int zle[2];
int nieb = 0;
int n,q;
void add(int i,char z,int val){
  if(z == 'C'){
    sum += val * 1;
    zle[i % 2] += val;
  }
  if(z == 'Z'){
    sum += val * 2;
    zle[(i + 1) % 2] += val;
  }
  if(z == 'N')
    nieb += val;
}
vector<int> dp[2];
const int P = 1e9 + 7;
void licz(){
  if(n == 1){
    if(nieb == 0){
      cout << "1\n";
    }else{
      cout << "2\n";
    }
  }else{
    int res = dp[1][nieb];
    res += dp[sum % 3 == 0][nieb];
    if(n & 1){
      if(zle[0] == 0) res --;
      if(zle[1] == 0) res --;
    }
    cout << (res % P + P) % P << "\n";
  }
}
inline void moduj(int &a){if(a >= P)a -= P;}

int32_t main(){
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout << fixed << setprecision(11);
  cerr << fixed << setprecision(6);
  string s;
  cin >> n >> q >> s;
  zle[0] = zle[1] = 0;
  dp[0].resize(n + 1);
  dp[1].resize(n + 1);
  dp[0][0] = 1;
  R(i,n){
    dp[0][i+1] = dp[1][i] * 2;
    dp[1][i+1] = dp[0][i] + dp[1][i];
    R(j,2)moduj(dp[j][i+1]);
  }
  R(i,n){
    add(i, s[i], 1);
  }
  licz();
  R(i,q){
    int id;
    char z;
    cin >> id >> z;
    id--;
    add(id, s[id], -1);
    s[id] = z;
    add(id, s[id], 1);
    licz();
  }
}