#include <bits/stdc++.h>
#pragma warning(disable : 4996)
#pragma comment(linker, "/stack:200000000")
#pragma GCC optimize("Ofast")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#pragma GCC optimize("-ffloat-store")
using namespace std;
clock_t time_p = clock();
void aryanc403() {
  time_p = clock() - time_p;
  cerr << "Time Taken : " << (float)(time_p) / CLOCKS_PER_SEC << "\n";
}
const long long int INF = 0xFFFFFFFFFFFFFFFL;
long long int seed;
mt19937 rng(seed = chrono::steady_clock::now().time_since_epoch().count());
inline long long int rnd(long long int l = 0, long long int r = INF) {
  return uniform_int_distribution<long long int>(l, r)(rng);
}
class CMP {
 public:
  bool operator()(pair<long long int, long long int> a,
                  pair<long long int, long long int> b) {
    return !(a.first < b.first || a.first == b.first && a.second <= b.second);
  }
};
void add(map<long long int, long long int> &m, long long int x,
         long long int cnt = 1) {
  auto jt = m.find(x);
  if (jt == m.end())
    m.insert({x, cnt});
  else
    jt->second += cnt;
}
void del(map<long long int, long long int> &m, long long int x,
         long long int cnt = 1) {
  auto jt = m.find(x);
  if (jt->second <= cnt)
    m.erase(jt);
  else
    jt->second -= cnt;
}
bool cmp(const pair<long long int, long long int> &a,
         const pair<long long int, long long int> &b) {
  return a.first < b.first || (a.first == b.first && a.second < b.second);
}
const long long int mod = 1000000007L;
long long int T, n, i, j, k, in, cnt, l, r, u, v, x, y;
long long int m, q, h;
string s;
map<long long int, long long int> a;
void add(long long int x, long long int v) {
  if (v == 0) return;
  while (x) {
    a[x] += v;
    x /= 2;
  }
}
long long int get(long long int x) {
  auto it = a.find(x);
  if (it == a.end()) return 0;
  return it->second;
}
long double fnd(long long int h) {
  long double ans = 0;
  long long int v = 1, mx = 0, x, y, t = get(1), H = h;
  h--;
  while (h >= 0) {
    x = get(2 * v);
    y = get(2 * v + 1);
    ;
    if ((x == y) || (t - x <= mx && t - y <= mx)) {
      ans += 2 * max({mx, t - x, t - y}) * (long double)(1LL << h);
      break;
    } else if (x > y) {
      ;
      ans += max(mx, t - y) * (1LL << h);
      mx = max(mx, t - x);
      t = x;
      v *= 2;
    } else {
      ans += max(mx, t - x) * (1LL << h);
      mx = max(mx, t - y);
      t = y;
      v = 2 * v + 1;
    }
    h--;
  }
  if (h == -1) {
    ans += max(mx, t);
  }
  ans /= (1LL << H);
  return ans;
}
int main(void) {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  {
    cin >> h >> q;
    while (q--) {
      cin >> s;
      if (s == "add") {
        cin >> x >> y;
        add(x, y);
      } else
        cout << std::fixed << std::setprecision(6) << fnd(h) << "\n";
    }
  }
  aryanc403();
  return 0;
}
