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#include<bits/stdc++.h>
#define FOR(i,a,b) for(int i=a;i<(int)b;++i)
#define FORD(i,a,b) for(int i=a;i>=(int)b;--i)
#define PB push_back
#define EB emplace_back
#define FI first
#define SE second
#define umap unordered_map
#define uset unordered_set
#define vi vector<int>
#define vvi vector<vi>
#define vll vector<ll>
#define vvll vector<vll>
#define vpii vector<pii>
#define pii pair<int, int>
#define pll pair<ll, ll>
#define ALL(X) (X).begin(),(X).end()
#ifndef DEBUG
#define endl (char)10
#endif
using namespace std;
using ll = long long;
using ld = long double;

template <class T>
istream& operator>> (istream& is, vector<T>& vec){
    FOR(i,0,vec.size()) is >> vec[i];
    return is;
}
template <class T>
ostream& operator<< (ostream& os, vector<T>& vec){
    for(auto& t : vec) os << t << " ";
    return os;
}
template<class T, class U>
ostream& operator<< (ostream& os, const pair<T, U>& p){
    os << p.FI << " " << p.SE;
    return os;
}
template<class T, class U>
istream& operator>> (istream& is, pair<T, U>& p){
    is >> p.FI >> p.SE;
    return is;
}

template<const int MOD>
struct MintBase {
    static const int P = MOD;
    ll x;

    MintBase<MOD>() : x(0){}
    MintBase<MOD>(ll x_) : x(normalize(x_)) {}
    MintBase<MOD>(const MintBase<MOD>& o) : x(o.x) {};

    static ll normalize(ll x_) {
        x_ %= MOD;
        if (x_ < 0) x_ += MOD;
        return x_;
    }

    bool operator==(const MintBase<MOD>& o) const {
        return x == o.x;
    }

    MintBase<MOD> operator+ (const MintBase<MOD>& o) const {
         MintBase<MOD> res(*this);
         res += o;
         return res;
    }

    MintBase<MOD> operator- (const MintBase<MOD>& o) const {
         MintBase<MOD> res(*this);
         res -= o;
         return res;
    }

    MintBase<MOD>& operator+= (const MintBase<MOD>& o) {
        x += o.x;
        if (x >= MOD) x -= MOD;
        return *this;
    }

    MintBase<MOD>& operator++() {
        x += 1;
        if (x == MOD) x = 0;
        return *this;
    }

    MintBase<MOD>& operator--() {
        if (x == 0) x = MOD - 1;
        else x--;
        return *this;
    }

    MintBase<MOD>& operator-= (const MintBase<MOD>& o) {
        x -= o.x;
        if (x < 0) x += MOD;
        return *this;
    }

    MintBase<MOD> operator* (const MintBase<MOD>& o) const {
        return MintBase<MOD>(x * o.x);
    }

    MintBase<MOD>& operator*= (const MintBase<MOD>& o) {
        x *= o.x;
        x %= MOD;
        return *this;
    }

    MintBase<MOD> operator/ (const MintBase<MOD>& o) const {
        return (*this) * (o.inv());
    }

    MintBase<MOD> inv() const {
        // assuming MOD is prime
        return pow(MOD - 2);
    }

    MintBase<MOD> pow(int k) const {
        MintBase<MOD> ans = 1;
        MintBase<MOD> pom = *this;
        while(k > 0){
            if (k % 2 == 1) ans = ans * pom;
            pom = pom * pom;
            k /= 2;
        }
        return ans;
    }
};
template<const int MOD>
ostream& operator<< (ostream& os, const MintBase<MOD>& mint){
    return os << mint.x;
}
template<const int MOD>
istream& operator>> (istream& is, MintBase<MOD>& mint){
    return (is >> mint.x);
}
using Mint = MintBase<1'000'000'007>;
//using Mint = MintBase<998'244'353>;
using vmi = vector<Mint>;


int main () {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    int n, q;
    string s;
    cin >> n >> q >> s;
    vi B(n);
    int popcnt = 0;
    int pytcnt = 0;
    vvi loks(2, vi(2, 0));
    FOR(i,0,n){
        if (s[i] == 'Z'){
            B[i] = 0;
            loks[0][i % 2]++;
        }
        if (s[i] == 'C'){
            B[i] = 1;
            popcnt++;
            loks[1][i % 2]++;
        }
        if (s[i] == 'N'){
            B[i] = -1;
            pytcnt++;
        }
    }
    vector<vmi> P(n + 1, vmi(3, 0));
    P[0][0] = 1;
    FOR(i,1,n+1){
        FOR(j,0,3){
            FOR(k,0,3){
                if (j != (k + 1) % 3) P[i][k] += P[i - 1][j];
            }
        }
    }

    FOR(i,0,q+1){
        Mint ans = 0;
        FOR(j,0,3) if ((n + popcnt + j) % 3 != 0) ans += P[pytcnt][j];
        //cout << B << ": " << popcnt << " " << ans << endl;
        if (n % 2 == 1){
            if (loks[0][0] == 0 && loks[1][1] == 0) --ans;
            if (loks[0][1] == 0 && loks[1][0] == 0) --ans;
        }
        cout << ans << endl;
        if (i != q){
            int idx; char c;
            cin >> idx >> c;
            idx--;
            if (B[idx] == -1){
                pytcnt--;
            } else if (B[idx] == 0){
                loks[0][idx % 2]--;
            } else {
                loks[1][idx % 2]--;
                popcnt--;
            }
            if (c == 'N'){
                B[idx] = -1;
                pytcnt++;
            } else if (c == 'Z'){
                B[idx] = 0;
                loks[0][idx % 2]++;
            } else {
                B[idx] = 1;
                loks[1][idx % 2]++;
                popcnt++;
            }
        }
    }
}