#include<bits/stdc++.h>
namespace {
#pragma GCC diagnostic ignored "-Wunused-function"
#include<atcoder/all>
#pragma GCC diagnostic warning "-Wunused-function"
using namespace std;
using namespace atcoder;
#define rep(i,n) for(int i = 0; i < (int)(n); i++)
#define rrep(i,n) for(int i = (int)(n) - 1; i >= 0; i--)
#define all(x) begin(x), end(x)
#define rall(x) rbegin(x), rend(x)
template<class T> bool chmax(T& a, const T& b) { if (a < b) { a = b; return true; } else return false; }
template<class T> bool chmin(T& a, const T& b) { if (b < a) { a = b; return true; } else return false; }
using ll = long long;
using P = pair<int,int>;
using VI = vector<int>;
using VVI = vector<VI>;
using VL = vector<ll>;
using VVL = vector<VL>;

struct S {
  bool to[2];
  int into[2], outfrom[2];
  ll res;
};
S op(S x, S y) {
  S z{};
  rep(i, 2) {
    z.to[i] = y.to[x.to[i]];
    z.into[y.to[i]] += x.into[i];
    z.into[i] += y.into[i];
    z.outfrom[i] += x.outfrom[i];
    z.outfrom[i] += y.outfrom[x.to[i]];
    z.res += (ll)x.into[i] * y.outfrom[i];
  }
  z.res += x.res + y.res;
  return z;
}
S e() {
  S s;
  rep(i, 2) s.to[i] = i;
  return s;
}

} int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int n, q;
  cin >> n >> q;
  string x;
  cin >> x;
  segtree<S, op, e> seg([&]() {
    vector<S> init((n + 1) / 2);
    for (int i = -1; i < n; i += 2) {
      S s{};
      char op = i == -1 ? '+' : x[i];
      bool val = x[i+1] == 'T';
      rep(i, 2) {
        int j = op == '+' ? i | val : op == '*' ? i & val : i ^ val;
        s.to[i] = j;
        s.outfrom[i] = j;
      }
      s.into[val] = 1;
      s.res = val;
      init[(i + 1) / 2] = s;
    }
    return init;
  }());
  rep(_, q) {
    int l, r;
    cin >> l >> r;
    l--;
    l = (l + 1) / 2;
    r = (r + 1) / 2;
    cout << seg.prod(l, r).res << '\n';
  }
}