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#include <cstdio>
#include <vector>
#include <algorithm>
#include <string>
#include <cstring>
#include <sstream>
#include <iostream>
#include <map>
#include <cmath>
#include <set>
#include <queue>
#include <numeric>
#include <ctime>

using namespace std;
typedef long long LL;
#define INF 1000000000
#define SZ(v) ((int)(v).size())
#define FOR(i,a,b) for(int i=(a);i<(b);i++)
#define FORE(i,a,b) for(int i=(a);i<=(b);i++)
#define FS first
#define SD second
#define MP make_pair
#define ZERO(t) memset(t, 0, sizeof(t))
#define MINUS(t) memset(t, -1, sizeof(t))
#define MOD 1000000007
#define MIN(_a,_b) ((_a)<(_b)?(_a):(_b))
#define MAX(_a,_b) ((_a)>(_b)?(_a):(_b))


int M[100][100][2];

char S[100], S2[100];
int n;

int go(int a, int b, int c) {
  if (M[a][b][c] != -1) return M[a][b][c];
  if (a == b) {
    return (S[a] == 'C') == c;
  }
  int res = 0;
  FOR(s, a, b) {
    if (go(a, s, (c + 1) % 2)  && go(s+1,b, (c + 1) %2)) res = 1;
  }
  return M[a][b][c] = res;
}

int go() {
  int res = 0;
  int k = 0;
  FOR(i,0,n) {
    k += S[i] == 'N';
  }
  if (k == 0) {
    MINUS(M);
    return go(0, n - 1, 0) + go(0, n - 1, 1);
  }
  else {
    FOR(i,0,n) S2[i] = S[i];

    FOR(m,0,1<<k) {
      int k = 0;
      FOR(i,0,n) {
        if (S2[i] == 'N') {
          if ((m>>k)&1) S[i] = 'C';
          else S[i] = 'Z';
          ++k;
        }
        else S[i] = S2[i];
      }
      MINUS(M);
      res += go(0, n - 1, 0) + go(0, n - 1, 1);
    }
    FOR(i,0,n) S[i] = S2[i];
    return res;
  }
}


int main() {
  int q; scanf("%d%d", &n, &q);
  scanf("%s", S);
  
  printf("%d\n", go());
  
  FOR(i,0,q) {
    int idx;
    char c;
    scanf("%d %c", &idx, &c);
    S[idx - 1] = c;
    MINUS(M);
    printf("%d\n", go());
  }
}