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#include <bits/stdc++.h>
#define ll long long

using namespace std;

ll mod = 1e9+7;

ll dp[200011][3];
int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(nullptr);
    cout.tie(nullptr);
    ll n, q; cin>>n>>q;
    ll ileC=0, ileZ=0, ileN=0;
    ll parC=0, parZ=0;
    dp[0][0] = 1;
    for(ll i = 1; i <= n; i++){
        dp[i][0] = (dp[i-1][1] + dp[i-1][2])%mod;
        dp[i][1] = (dp[i-1][0] + dp[i-1][2])%mod;
        dp[i][2] = (dp[i-1][1] + dp[i-1][0])%mod;
    }
    string s; cin>>s;
    for(ll i = 0; i < n; i++){
        if(s[i]=='C') ileC++;
        if(s[i]=='Z') ileZ++;
        if(s[i]=='N') ileN++;
        if(i%2==0){
            if(s[i]=='C') parC++;
            if(s[i]=='Z') parZ++;
        }
    }
    //cout<<ileC<<" "<<ileZ<<" "<<ileN<<" "<<parC<<" "<<parZ<<'\n';
    ll out = dp[ileN][(ileC-ileZ+3*n+1)%3]+dp[ileN][(ileC-ileZ+3*n+2)%3];
    if((ileC-ileZ+3*n)%3 >= 0 && n%2 == 1){
        if(parC==0&&parZ==ileZ) out--;
        if(parZ==0&&parC==ileC) out--;
    }

    out+=mod;
    cout<<out%mod<<'\n';
    for(ll i = 0; i < q; i++){
        ll x; char c;
        cin>>x>>c;
        x--;
        if(s[x]=='C') ileC--;
        if(s[x]=='Z') ileZ--;
        if(s[x]=='N') ileN--;
        if(x%2==0){
            if(s[x]=='C') parC--;
            if(s[x]=='Z') parZ--;
        }
        s[x] = c;
        if(s[x]=='C') ileC++;
        if(s[x]=='Z') ileZ++;
        if(s[x]=='N') ileN++;
        if(x%2==0){
            if(s[x]=='C') parC++;
            if(s[x]=='Z') parZ++;
        }
        out = dp[ileN][(ileC-ileZ+3*n+1)%3]+dp[ileN][(ileC-ileZ+3*n+2)%3];
        if((ileC-ileZ+3*n)%3 >=0  && n%2 == 1){
            if(parC==0&&parZ==ileZ) out--;
            if(parZ==0&&parC==ileC) out--;
        }
        out+=mod;
        cout<<out%mod<<'\n';
    }
    return 0;
}