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

typedef long long LL;
typedef long double LD;
typedef pair<int, int> PII;
typedef pair<LL, LL> PLL;

#define all(x) (x).begin(), (x).end()
#define sz(x) (int)(x).size()

template<typename _T> inline void _DBG(const char *s, _T x) { cerr << s << " = " << x << "\n"; }
template<typename _T, typename... args> void _DBG(const char *s, _T x, args... a) { while(*s != ',') cerr << *s++; cerr << " = " << x << ','; _DBG(s + 1, a...); }

#ifdef LOCAL
#define _upgrade ios_base::sync_with_stdio(0);
#define DBG(...) _DBG(#__VA_ARGS__, __VA_ARGS__)
#else
#define _upgrade ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define DBG(...) (__VA_ARGS__)
#define cerr if(0) cout
#endif

// ********************** CODE ********************** //

const int N = 2e5 + 7;
const int M = 1e9 + 7;

int n, q, dp[N][3];
string s;

int cnt_c[3], cnt_z[3], cnt_n[3];

void update_cnt(char c, int val, int i)
{
    if (c == 'C')
    {
        cnt_c[i % 2] += val;
        cnt_c[2] += val;
    }
    if (c == 'Z')
    {
        cnt_z[i % 2] += val;
        cnt_z[2] += val;
    }
    if (c == 'N')
    {
        cnt_n[i % 2] += val;
        cnt_n[2] += val;
    }
}

int calc_ans()
{
    int r = ((cnt_c[2] - cnt_z[2]) % 3 + 3) % 3;
    int t = (dp[cnt_n[2]][0] + dp[cnt_n[2]][1] + dp[cnt_n[2]][2] - dp[cnt_n[2]][r]) % M;
    if (n % 2 == 1 && n > 1 && cnt_c[0] == 0 && cnt_z[1] == 0)
        t = (t + M - 1) % M;
    if (n % 2 == 1 && n > 1 && cnt_c[1] == 0 && cnt_z[0] == 0)
        t = (t + M - 1) % M;
    return t;
}

int main()
{
    _upgrade
    
    cin >> n >> q >> s;
    
    dp[0][0] = 1;
    for (int i = 1; i <= n; i++)
    {
        dp[i][0] = (dp[i - 1][1] + dp[i - 1][2]) % M;
        dp[i][1] = (dp[i - 1][0] + dp[i - 1][2]) % M;
        dp[i][2] = (dp[i - 1][0] + dp[i - 1][1]) % M;
    }

    for (int i = 0; i < n; i++)
        update_cnt(s[i], +1, i);
    cout << calc_ans() << "\n";
    
    while (q--)
    {
        int id;
        char c;
        cin >> id >> c;

        id--;
        update_cnt(s[id], -1, id);
        s[id] = c;
        update_cnt(s[id], +1, id);

        cout << calc_ans() << "\n";
    }

    return 0;
}