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#include<cstdio>
#include<set>
#include<string>
#include<iostream>
#include<cstdlib>
using namespace std;
const int N=200005,M=555555,K=10,P=1000000007;
const string state[K]={"C","Z","CC","ZZ","CZ","ZC","CZC","ZCZ","CCC","ZZZ"};
int n,q,i,j,combine[K][K],v[M][K],pos[N];char s[N];
string simplify(string s){
	int n=s.size();
	for(int i=0;i+1<n;i++)if(s[i]==s[i+1]){
		if((i&&s[i-1]!=s[i])||(i+2<n&&s[i+1]!=s[i+2])){
			string t;
			for(int j=0;j<i;j++)t.push_back(s[j]);
			t.push_back('C'+'Z'-s[i]);
			for(int j=i+2;j<n;j++)t.push_back(s[j]);
			return simplify(t);
		}
	}
	if(s[0]==s[1]){
		while(n>4)n-=3;
		if(n==4){
			n=2;
			for(int i=0;i<n;i++)s[i]='C'+'Z'-s[i];
		}
	}else while(n>3)n-=2;
	s.resize(n);
	return s;
}
inline bool check(string s){
	int n=s.size();
	if(n==1)return 1;
	if(n==2)return s[0]==s[1];
	return 0;
}
inline int getstate(string s){
	for(int i=0;i<K;i++)if(state[i]==s)return i;
	return -1;
}
inline void init(int x,char p){
	for(int i=0;i<K;i++)v[x][i]=0;
	if(p=='C'||p=='N')v[x][0]=1;
	if(p=='Z'||p=='N')v[x][1]=1;
}
inline void merge(int*a,int*b,int*c){
	for(int i=0;i<K;i++)c[i]=0;
	for(int i=0;i<K;i++)if(a[i])for(int j=0;j<K;j++)if(b[j]){
		int k=combine[i][j];
		c[k]=(c[k]+1LL*a[i]*b[j])%P;
	}
}
void build(int x,int a,int b){
	if(a==b){
		init(pos[a]=x,s[a]);
		return;
	}
	int mid=(a+b)>>1;
	build(x<<1,a,mid);
	build(x<<1|1,mid+1,b);
	merge(v[x<<1],v[x<<1|1],v[x]);
}
inline void modify(int x,char p){
	init(x=pos[x],p);
	for(x>>=1;x;x>>=1)merge(v[x<<1],v[x<<1|1],v[x]);
}
inline void getans(){
	int ans=0;
	for(int i=0;i<4;i++)(ans+=v[1][i])%=P;
	printf("%d\n",ans);
}
namespace FIND{
	set<string>T;
	set<string>F;
	const int LIM=16;
	int cnt;
	void dfs(string s){
		if(!check(simplify(s))){
			puts("WA");
			cout<<s<<" "<<simplify(s)<<endl;
			exit(0);
		}
		if(s.size()>LIM)return;
		if(T.find(s)!=T.end())return;
		if(s.size()==LIM)cnt++;
		T.insert(s);
		for(int i=0;i<s.size();i++){
			string t;
			for(int j=0;j<i;j++)t.push_back(s[j]);
			if(s[i]=='C'){
				t+="ZZ";
			}else{
				t+="CC";
			}
			for(int j=i+1;j<s.size();j++)t.push_back(s[j]);
			dfs(t);
		}
	}
	void go(string s){
		if(s.size()>LIM)return;
		F.insert(simplify(s));
		s.push_back('C');
		go(s);
		s[s.size()-1]='Z';
		go(s);
	}
	void gao(){
		dfs("C");
		dfs("Z");
		puts("DONE");
		printf("%d\n",cnt);
		/*for(set<string>::iterator it=T.begin();it!=T.end();it++){
			cout<<*it<<endl;
		}*/
		go("C");
		go("Z");
		for(set<string>::iterator it=F.begin();it!=F.end();it++){
			cout<<*it<<endl;
		}
	}
}
int main(){
	/*string s;
	cin>>s;
	cout<<simplify(s);*/
	//FIND::gao();
	for(i=0;i<K;i++)for(j=0;j<K;j++)combine[i][j]=getstate(simplify(state[i]+state[j]));
	scanf("%d%d%s",&n,&q,s+1);
	build(1,1,n);
	getans();
	while(q--){
		scanf("%d%s",&i,s);
		modify(i,s[0]);
		getans();
	}
}