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//Jakub Trela
#include <bits/stdc++.h>
using namespace std;

typedef long long LL;

int M = 1<<18;
int T=1;
int MOD = 1e9+7;

vector<int> treeL(2*M+1,-1);
vector<int> lazyL(2*M+1);
vector<int> treeR(2*M+1,-1);
vector<int> lazyR(2*M+1);

void updateL(int a, int b, int val){
    if(a==0)return;
    a+=M;
    b+=M;
    while(a<=b){
        if(a%2==1){
            treeL[a]=val;
            lazyL[a]=T;
            a++;
        }
        if(b%2==0){
            treeL[b]=val;
            lazyL[b]=T;
            b--;
        }
        a/=2;
        b/=2;
    }
    T++;
}

int queryL(int a){
    a+=M;
    int maxi=-1,res=0;
    while(a>=1){
        if(lazyL[a]>maxi){
            maxi=lazyL[a];
            res=treeL[a];
        }
        a/=2;
    }
    return res;
}
void updateR(int a, int b, int val){
    if(a==0)return;
    a+=M;
    b+=M;
    while(a<=b){
        if(a%2==1){
            treeR[a]=val;
            lazyR[a]=T;
            a++;
        }
        if(b%2==0){
            treeR[b]=val;
            lazyR[b]=T;
            b--;
        }
        a/=2;
        b/=2;
    }
    T++;
}

int queryR(int a){
    a+=M;
    int maxi=-1,res=0;
    while(a>=1){
        if(lazyR[a]>maxi){
            maxi=lazyR[a];
            res=treeR[a];
        }
        a/=2;
    }
    return res;
}

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    // -----------------------------------------------------------------------------------

    vector<vector<int>> dp(2e5+1,vector<int>(3));
    dp[1]={0,1,1};
    for(int i=2;i<=2e5;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][0]+dp[i-1][1])%MOD;
    }

    int n,q;
    cin>>n>>q;

    vector<char> tab(n+2);
    for(int i=1;i<=n;i++)cin>>tab[i];

    //brut
    // if(n*q<=1000000){
        for(int j=0;j<=q;j++){
            if(j>0){
                int a;
                char c;
                cin>>a>>c;
                tab[a]=c;
            }
            int sum=0;
            int firstC=-1,firstZ=-1;
            bool czyPara=false;
            int countN=0;
            for(int i=1;i<n;i++){
                if(tab[i]=='C' && tab[i+1]=='C')czyPara=true;
                if(tab[i]=='Z' && tab[i+1]=='Z')czyPara=true;
            }
            vector<pair<int,int>> lewo(n+2),prawo(n+2);
            bool czyParaN=false;
            for(int i=1;i<=n;i++){
                if(tab[i]=='C'){lewo[i]={1,i};sum=(sum+1)%3;firstC=i;}
                else if(tab[i]=='Z'){lewo[i]={2,i};sum=(sum+2)%3;firstZ=i;}
                else{ lewo[i]={lewo[i-1].first,lewo[i-1].second+1};countN++;}
            }
            for(int i=n;i>=1;i--){
                if(tab[i]=='C')prawo[i]={1,i};
                else if(tab[i]=='Z')prawo[i]={2,i};
                else prawo[i]={prawo[i+1].first,prawo[i+1].second+1};
            }
            for(int i=1;i<=n;i++){
                if(tab[i]=='N'){
                    if(lewo[i].first==0 || prawo[i].first==0)continue;
                    if(lewo[i].first==prawo[i].first && prawo[i].second%2==0)czyParaN=true;
                    if(lewo[i].first!=prawo[i].first && prawo[i].second%2==1)czyParaN=true;
                }
            }
            if(countN==0 && !czyPara){
                cout<<0<<endl;
                continue;
            }
            int res=(dp[countN][0]+dp[countN][1]+dp[countN][2]-dp[countN][(3-sum)%3])%MOD; 
            if(n%2==1)
            if(countN==n)res-=2;
            if(n%2==1)
            if(!czyPara && !czyParaN){
                if(firstC!=-1){
                    if(firstC%2==1){
                        if((3-sum)%3!=1)res--;
                    }else{
                        if((3-sum)%3!=2)res--;
                    }
                }else if(firstZ!=-1){
                    if(firstZ%2==0){
                        if((3-sum)%3!=1)res--;
                    }else{
                        if((3-sum)%3!=2)res--;
                    }
                }
            }
            res+=MOD;
            res%=MOD;
            cout<<res<<endl;
        }
    // }

    // -----------------------------------------------------------------------------------

    return 0;
}