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//#pragma GCC optimize("Ofast")
//#pragma GCC target ("avx2")
//#pragma GCC optimization ("O3")
//#pragma GCC optimization ("unroll-loops")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#include<bits/stdc++.h>
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>
//using namespace __gnu_pbds;
using namespace std;
//typedef tree<pair<int,int>,null_type,less<pair<int,int>>,rb_tree_tag,tree_order_statistics_node_update>ordered_set;
#define ll long long
#define ull unsigned long long int
#define pb push_back
#define mp make_pair
#define vi vector<int>
#define pii pair<int,int>
#define pss pair<short,short>
#define pld pair<long double,long double >
#define ld long double
#define piii  pair<pii,int>
#define vii vector<pair<int,int> >
#define st first
#define nd second
#define pll pair<ll,ll>
#define speed ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define M_PI 3.14159265358979323846
//#define int long long
const int mod=1000000007;
//const int mod=1009;
//const int mod=998244353;
const int inf=1000000009;
const long long INF=1000000000000000009;
const long long big=1000000000000000;
const long double eps=0.000000000000000000001;
int n,q;
string napis;
int qm=0;
int DP[200005][3];
int O[2][2];
int match(char c){
    if(c=='Z')
        return 0;
    return 1;
}
void wstaw(char c,int poz, int m){
    if(c=='N')
        qm+=m;
    else
        O[match(c)][poz%2]+=m;
}
int oblicz(){
    if(n==1){
        if(napis[1]=='N')
            return 2;
        return 1;
    }
    int zielone=O[0][0]+O[0][1];
    int niebieskie=O[1][0]+O[1][1];
    int roznica=zielone-niebieskie;
    roznica+=3*n;
    roznica%=3;
    int wynik=0;
    for(int j=0;j<3;j++){
        int cur=(roznica+j)%3;
        if(cur){
            wynik+=DP[qm][j];
            wynik%=mod;
        }
    }
    if(n%2==0)
        return wynik;
    if(qm==n){
        wynik=wynik-2+mod;
        wynik%=mod;
    }
    else{
        int czy=0;
        if(O[0][0]==0||O[0][1]==0)
            czy++;
        if(O[1][0]==0||O[1][1]==0)
            czy++;
        if(czy==2){
            wynik=wynik-1+mod;
            wynik%=mod;
        }
    }
    return wynik;

}
void solve()
{
    cin>>n>>q>>napis;
    napis="#"+napis;
    DP[0][0]=1;
    for(int i=1;i<=n;i++){
        for(int j=0;j<3;j++){
            DP[i][j]=DP[i-1][(j+1)%3]+DP[i-1][(j-1+3)%3];
            DP[i][j]%=mod;
        }
    }
    for(int i=1;i<=n;i++){
        wstaw(napis[i],i,1);
    }
    cout<<oblicz()<<"\n";
    for(int i=1;i<=q;i++){
        int poz;
        char c;
        cin>>poz>>c;
        wstaw(napis[poz],poz,-1);
        napis[poz]=c;
        wstaw(c,poz,1);
        cout<<oblicz()<<"\n";
    }


}
    
int32_t main(){
    speed
    int t = 1;
    //cin >> t;
    while(t--){
        solve();
    }
    return 0;
}