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#include <bits/stdc++.h>
#define zesp complex<long double>
using namespace std;
const long long mod=1e9+7;
const long long mod_inv=333333336;
const int maxn=200003;
class eisen_mod
{
    public:
    long long re, im;
    eisen_mod(long long a, long long b=0)
    {
        re = a%mod;
        if(re<0)
            re+=mod;
        im = b%mod;
        if(im<0)
            im+=mod;
    }
    eisen_mod operator+(const eisen_mod z) {return eisen_mod(re+z.re, im+z.im);}
    eisen_mod operator-(const eisen_mod z) {return eisen_mod(re-z.re, im-z.im);}
    eisen_mod operator*(const eisen_mod z) {return eisen_mod(re*z.re-im*z.im, im*z.re+re*z.im-im*z.im);}
};
eisen_mod omega(0,1);
eisen_mod sp(eisen_mod a, int n)
{
    if(n==0)
        return eisen_mod(1);
    eisen_mod pom=sp(a,n/2);
    if(n%2 == 0)
        return pom*pom;
    return pom*pom*a;
}
long long root_filter(int m, int n)
{
    m%=3;
    if(m<0)
    m+=3;
    if(m == 0)
    {
        return ((sp(eisen_mod(2,0),n) + sp(eisen_mod(1,1),n) + sp(eisen_mod(0,-1),n)) * eisen_mod(mod_inv)).re;
    }
    if(m == 1)
    {
        return ((sp(eisen_mod(2,0),n) + omega*omega*sp(eisen_mod(1,1),n) + omega*sp(eisen_mod(0,-1),n)) * eisen_mod(mod_inv)).re;
    }
    if(m == 2)
    {
        return ((sp(eisen_mod(2,0),n) + omega*sp(eisen_mod(1,1),n) + omega*omega*sp(eisen_mod(0,-1),n)) * eisen_mod(mod_inv)).re;
    }
}
long long wzorek(int C, int Z, int B, int deviation, int antideviation, int n)
{
    //cout<<C<<" "<<Z<<" "<<deviation<<" "<<antideviation<<" "<<n<<"\n";
    int m = 2*(B-Z+C);
    long long odp = root_filter(m+1, B)+root_filter(m+2, B);
    if((n%2 == 1)&&(deviation == n))
        odp--;
    if((n%2 == 1)&&(antideviation == n))
        odp--;
    odp%=mod;
    if(odp<0)
        odp+=mod;
    return odp;
}
int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(NULL);
    cout.tie(NULL);
    int n,q;
    cin>>n>>q;
    string s;
    cin>>s;
    if(n==1)
    {
        if(s[0]=='N')
            cout<<"2\n";
        else
            cout<<"1\n";
        while(q--)
        {
            int x;
            char zn;
            cin>>x>>zn;
            s[0]=zn;
            if(s[0]=='N')
                cout<<"2\n";
            else
                cout<<"1\n";
        }
    }


    else
    {


    int C=0,Z=0,B=0;
    int deviation=0;
    int antideviation=0;
    bitset<maxn> c,nb;
    for(int i=0;i<n;i++)
    {
        if(s[i]=='C')
        {
            c[i]=1;
            nb[i]=1;
            C++;
        }
        if(s[i]=='Z')
        {
            c[i]=0;
            nb[i]=1;
            Z++;
        }
        if(s[i]=='N')
        {
            c[i]=0;
            nb[i]=0;
            B++;
        }
        if((c[i] == (i%2)) || (nb[i] == 0))
            deviation++;
        if((c[i] != (i%2)) || (nb[i] == 0))
            antideviation++;
    }
    cout<<wzorek(C, Z, B, deviation, antideviation, n)<<"\n";
    int x;
    char zn;
    while(q--)
    {
        cin>>x>>zn;
        x--;
        if((c[x] == (x%2)) || (nb[x] == 0))
            deviation--;
        if((c[x] != (x%2)) || (nb[x] == 0))
            antideviation--;
        if((c[x] == 0)&&(nb[x]==1))
            Z--;
        if(c[x] == 1)
            C--;
        if(nb[x]==0)
            B--;
        if(zn == 'Z')
        {
            c[x]=0;
            nb[x]=1;
            Z++;
        }
        if(zn == 'C')
        {
            c[x]=1;
            nb[x]=1;
            C++;
        }
        if(zn == 'N')
        {
            c[x]=0;
            nb[x]=0;
            B++;
        }
        if((c[x] == (x%2)) || (nb[x] == 0))
            deviation++;
        if((c[x] != (x%2)) || (nb[x] == 0))
            antideviation++;
        cout<<wzorek(C, Z, B, deviation, antideviation, n)<<"\n";
    }


    }
}