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#include<bits/stdc++.h>
 
//#pragma GCC optimize("Ofast")
//#pragma GCC optimize("trapv")
 
#define st first
#define nd second
#define pb push_back
#define pp pop_back
#define eb emplace_back
#define mp(a, b) make_pair(a, b)
#define all(x) (x).begin(), (x).end()
#define rev(x) reverse(all(x))
#define sor(x) sort(all(x))
#define sz(x) (int)(x).size()
#define rsz(x) resize(x)
 
using namespace std;
 
///~~~~~~~~~~~~~~~~~~~~~~~~~~
 
template <typename H, typename T> 
ostream& operator<<(ostream& os, pair<H, T> m){
	return os <<"("<< m.st<<", "<<m.nd<<")";
}
template <typename H> 
ostream& operator<<(ostream& os, vector<H> V){
	os<<"{";
	for(int i=0; i<V.size(); i++){
		if(i)os<<" ";
		os<<V[i];
	}
	os<<"}";
	return os;
}
 
void debug(){cerr<<"\n";}
template <typename H, typename... T>
void debug(H h, T... t) {cerr<<h; if (sizeof...(t)) cerr << ", "; debug(t...);}
#define deb(x...) cerr<<#x<<" = ";debug(x);
 
///~~~~~~~~~~~~~~~~~~~~~~~~~
 
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<pii > vii;
typedef vector<ll> vl;
typedef vector<pll> vll;
typedef string str;
 
#define BOOST ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
 
mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
 
const int N=2e5+5, INF=1e9+5, mod=1e9+7;
int a, b[2], c[2];
int n;
str s;
void upd(int i, int typ){
	if(s[i]=='N')a+=typ;
	if(s[i]=='C')b[i&1]+=typ;
	if(s[i]=='Z')c[i&1]+=typ;
}
int pot[N];
int ans(){
	if(n==1){
		return a+1;
	}
	int s=b[0]+b[1]+(c[0]+c[1])*2;
	s%=3;
	//deb(s, a);
	int res=pot[a];
	if(a&1){
		if(!s)res++;
	}
	else{
		if(s)res++;
	}
	//deb(res);
	if(n&1){
		if(!c[0]&&!b[1])res--;
		if(!c[1]&&!b[0])res--;		
	}
	if(res<0)res+=mod;
	if(res>=mod)res-=mod;
	return res;
}
int main(){
	//BOOST;
	for(int i=1; i<N; i++){
		pot[i]=(pot[i-1]*2)%mod;
		if((i&1))pot[i]++;
	}
	//deb(pot[2], pot[3]);
	int q;
	cin>>n>>q;
	cin>>s;
	for(int i=0; i<n; i++){
		upd(i, 1);
	}
	cout<<ans()<<"\n";
	while(q--){
		int i;
		char l;
		cin>>i>>l;
		i--;
		upd(i, -1);
		s[i]=l;
		upd(i, 1);
		cout<<ans()<<"\n";
	}
}