#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, m;
  cin >> n >> m;
  vector<char> s(n);
  long long ans = 0;
  for (int i = 0; i < n; ++i) {
    cin >> s[i];
    if (i > 0 and s[i] == '.' and s[i - 1] == '.') ++ans;
  }
  for (int i = 0; i < m; ++i) {
    int pos;
    cin >> pos;
    --pos;
    char c;
    cin >> c;
    if (c == '.' and s[pos] != '.') {
      if (pos > 0 and s[pos - 1] == '.') ++ans;
      if (pos < n and s[pos + 1] == '.') ++ans;
    } else if (c != '.' and s[pos] == '.') {
      if (pos > 0 and s[pos - 1] == '.') --ans;
      if (pos < n and s[pos + 1] == '.') --ans;
    }
    s[pos] = c;
    cout << ans << '\n';
  }
}
