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#include <bits/stdc++.h>
#define F first
#define S second
#define ll long long

using namespace std;

const int MAXN = 2e5 + 99;
const ll MOD = 1e9 + 7;

int t[MAXN];
int g[MAXN][3];
int cntN;
pair<int,int> cntZ,cntC;
int n,q;

void pre(){
	g[0][0] = 0;
	g[0][1] = 1;
	g[0][2] = 1;
	for(int i = 1; i < MAXN; i++){
		g[i][0] = (g[i-1][1] + g[i-1][2]) % MOD;
		g[i][1] = (g[i-1][0] + g[i-1][2]) % MOD;
		g[i][2] = (g[i-1][0] + g[i-1][1]) % MOD;
	}
}

void solve(){
	int sumZ = cntZ.F + cntZ.S;
	int sumC = cntC.F + cntC.S;
	ll wynik = (g[cntN][((sumZ - sumC) % 3 + 3 ) % 3]);
	if(cntZ.F == 0 && cntC.S == 0 && n % 2 != 0 && n > 1)
		wynik--;
	if(cntZ.S == 0 && cntC.F == 0 && n % 2 != 0 && n > 1)
		wynik--;
	cout << max(wynik,(ll)0) << "\n";
}

int main(){
	cntN = 0;
	cntZ = cntC = {0,0};
	cin >> n >> q;
	pre();
	for(int i = 0; i < n; i++){
		char c;
		cin >> c;
		if(c == 'C'){
			t[i] = 0;
			cntC.F += (i % 2 == 0);
			cntC.S += (i % 2 == 1);
		}else if(c == 'Z'){
			t[i] = 1;
			cntZ.F += (i % 2 == 0);
			cntZ.S += (i % 2 == 1);
		}else if(c == 'N'){
			t[i] = 2;
			cntN++;
		}
	}
	solve();

	for(int i = 0; i < q; i++){
		int j;
		char c;
		cin >> j >> c;
		if(t[j-1] == 0){
			cntC.F -= ((j - 1) % 2 == 0);
			cntC.S -= ((j - 1) % 2 == 1);
		}else if(t[j-1] == 1){
			cntZ.F -= ((j - 1) % 2 == 0);
			cntZ.S -= ((j - 1) % 2 == 1);
		}else if(t[j-1] == 2){
			cntN--;
		}
		if(c == 'C'){
			t[j - 1] = 0;
			cntC.F += ((j - 1) % 2 == 0);
			cntC.S += ((j - 1) % 2 == 1);
		}else if(c == 'Z'){
			t[(j - 1)] = 1;
			cntZ.F += ((j - 1) % 2 == 0);
			cntZ.S += ((j - 1) % 2 == 1);
		}else if(c == 'N'){
			t[(j - 1)] = 2;
			cntN++;
		}
		solve();
	}
}