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#include <bits/stdc++.h>
using namespace std;
#define sim template < class c
#define ris return * this
#define dor > debug & operator <<
#define eni(x) sim > typename \
  enable_if<sizeof dud<c>(0) x 1, debug&>::type operator<<(c i) {
sim > struct rge { c b, e; };
sim > rge<c> range(c i, c j) { return rge<c>{i, j}; }
sim > auto dud(c* x) -> decltype(cerr << *x, 0);
sim > char dud(...);
struct debug {
#ifdef LOCAL
~debug() { cerr << endl; }
eni(!=) cerr << boolalpha << i; ris; }
eni(==) ris << range(begin(i), end(i)); }
sim, class b dor(pair < b, c > d) {
  ris << "(" << d.first << ", " << d.second << ")";
}
sim dor(rge<c> d) {
  *this << "[";
  for (auto it = d.b; it != d.e; ++it)
	*this << ", " + 2 * (it == d.b) << *it;
  ris << "]";
}
#else
sim dor(const c&) { ris; }
#endif
};
#define imie(...) " [" << #__VA_ARGS__ ": " << (__VA_ARGS__) << "] "
// debug & operator << (debug & dd, P p) { dd << "(" << p.x << ", " << p.y << ")"; return dd; }

const int MOD = 1e9 + 7;

int main() {
	int n, q;
	scanf("%d%d", &n, &q);
	
	vector<vector<int>> dp(n+1, vector<int>(3));
	// dp[n][r] = (n choose r) + (n choose r+3) + ...
	dp[0][0] = 1;
	for (int k = 1; k <= n; k++) {
		for (int r = 0; r < 3; r++) {
			dp[k][r] = (dp[k-1][r] + dp[k-1][(r+2)%3]) % MOD;
		}
	}
	
	static char s[200123];
	scanf("%s", s);
	assert(n == (int) strlen(s));
	
	int marks = 0; // number of question marks (N)
	int sum3 = 0; // sum of +1 and +2
	vector<int> bad(2); // count of mismatches with 10101 or 01010
	
	auto CHANGE = [&](int i, int TYPE) {
		if (s[i] == 'N') {
			marks += TYPE;
		}
		sum3 += (s[i] == 'C' ? 2 : 1) * TYPE;
		if (s[i] == 'C') {
			bad[i%2] += TYPE;
		}
		if (s[i] == 'Z') {
			bad[(i+1)%2] += TYPE;
		}
	};
	auto INSERT = [&](int i) { CHANGE(i, +1); };
	auto ERASE = [&](int i) { CHANGE(i, -1); };
	
	for (int i = 0; i < n; i++) {
		INSERT(i);
	}
	
	auto query = [&]() {
		int answer = 0;
		for (int r = 0; r < 3; r++) {
			if ((sum3 + r) % 3 != 0) {
				answer = (answer + dp[marks][r]) % MOD;
			}
		}
		// consider 10101 and 01010
		if (n % 2 == 1 && n >= 3) {
			for (int b : bad) {
				if (b == 0) {
					answer = (answer + MOD - 1) % MOD;
				}
			}
		}
		printf("%d\n", answer);
	};
	
	query();
	
	while (q--) {
		int i;
		scanf("%d", &i);
		i--;
		ERASE(i);
		scanf(" %c", &s[i]);
		INSERT(i);
		query();
	}
}