#include <algorithm>
#include <array>
#include <bitset>
#include <cassert>
#include <chrono>
#include <cmath>
#include <complex>
#include <deque>
#include <forward_list>
#include <fstream>
#include <functional>
#include <iomanip>
#include <ios>
#include <iostream>
#include <limits>
#include <list>
#include <map>
#include <memory>
#include <numeric>
#include <optional>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <tuple>
#include <type_traits>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>
using namespace std;
using lint = long long;
using pint = pair<int, int>;
using plint = pair<lint, lint>;
struct fast_ios { fast_ios(){ cin.tie(nullptr), ios::sync_with_stdio(false), cout << fixed << setprecision(20); }; } fast_ios_;
#define ALL(x) (x).begin(), (x).end()
#define FOR(i, begin, end) for(int i=(begin),i##_end_=(end);i<i##_end_;i++)
#define IFOR(i, begin, end) for(int i=(end)-1,i##_begin_=(begin);i>=i##_begin_;i--)
#define REP(i, n) FOR(i,0,n)
#define IREP(i, n) IFOR(i,0,n)
template <typename T> bool chmax(T &m, const T q) { return m < q ? (m = q, true) : false; }
template <typename T> bool chmin(T &m, const T q) { return m > q ? (m = q, true) : false; }
const std::vector<std::pair<int, int>> grid_dxs{{1, 0}, {-1, 0}, {0, 1}, {0, -1}};
int floor_lg(long long x) { return x <= 0 ? -1 : 63 - __builtin_clzll(x); }
template <class T1, class T2> T1 floor_div(T1 num, T2 den) { return (num > 0 ? num / den : -((-num + den - 1) / den)); }
template <class T1, class T2> std::pair<T1, T2> operator+(const std::pair<T1, T2> &l, const std::pair<T1, T2> &r) { return std::make_pair(l.first + r.first, l.second + r.second); }
template <class T1, class T2> std::pair<T1, T2> operator-(const std::pair<T1, T2> &l, const std::pair<T1, T2> &r) { return std::make_pair(l.first - r.first, l.second - r.second); }
template <class T> std::vector<T> sort_unique(std::vector<T> vec) { sort(vec.begin(), vec.end()), vec.erase(unique(vec.begin(), vec.end()), vec.end()); return vec; }
template <class T> int arglb(const std::vector<T> &v, const T &x) { return std::distance(v.begin(), std::lower_bound(v.begin(), v.end(), x)); }
template <class T> int argub(const std::vector<T> &v, const T &x) { return std::distance(v.begin(), std::upper_bound(v.begin(), v.end(), x)); }
template <class IStream, class T> IStream &operator>>(IStream &is, std::vector<T> &vec) { for (auto &v : vec) is >> v; return is; }

template <class OStream, class T> OStream &operator<<(OStream &os, const std::vector<T> &vec);
template <class OStream, class T, size_t sz> OStream &operator<<(OStream &os, const std::array<T, sz> &arr);
template <class OStream, class T, class TH> OStream &operator<<(OStream &os, const std::unordered_set<T, TH> &vec);
template <class OStream, class T, class U> OStream &operator<<(OStream &os, const pair<T, U> &pa);
template <class OStream, class T> OStream &operator<<(OStream &os, const std::deque<T> &vec);
template <class OStream, class T> OStream &operator<<(OStream &os, const std::set<T> &vec);
template <class OStream, class T> OStream &operator<<(OStream &os, const std::multiset<T> &vec);
template <class OStream, class T> OStream &operator<<(OStream &os, const std::unordered_multiset<T> &vec);
template <class OStream, class T, class U> OStream &operator<<(OStream &os, const std::pair<T, U> &pa);
template <class OStream, class TK, class TV> OStream &operator<<(OStream &os, const std::map<TK, TV> &mp);
template <class OStream, class TK, class TV, class TH> OStream &operator<<(OStream &os, const std::unordered_map<TK, TV, TH> &mp);
template <class OStream, class... T> OStream &operator<<(OStream &os, const std::tuple<T...> &tpl);

template <class OStream, class T> OStream &operator<<(OStream &os, const std::vector<T> &vec) { os << '['; for (auto v : vec) os << v << ','; os << ']'; return os; }
template <class OStream, class T, size_t sz> OStream &operator<<(OStream &os, const std::array<T, sz> &arr) { os << '['; for (auto v : arr) os << v << ','; os << ']'; return os; }
template <class... T> std::istream &operator>>(std::istream &is, std::tuple<T...> &tpl) { std::apply([&is](auto &&... args) { ((is >> args), ...);}, tpl); return is; }
template <class OStream, class... T> OStream &operator<<(OStream &os, const std::tuple<T...> &tpl) { os << '('; std::apply([&os](auto &&... args) { ((os << args << ','), ...);}, tpl); return os << ')'; }
template <class OStream, class T, class TH> OStream &operator<<(OStream &os, const std::unordered_set<T, TH> &vec) { os << '{'; for (auto v : vec) os << v << ','; os << '}'; return os; }
template <class OStream, class T> OStream &operator<<(OStream &os, const std::deque<T> &vec) { os << "deq["; for (auto v : vec) os << v << ','; os << ']'; return os; }
template <class OStream, class T> OStream &operator<<(OStream &os, const std::set<T> &vec) { os << '{'; for (auto v : vec) os << v << ','; os << '}'; return os; }
template <class OStream, class T> OStream &operator<<(OStream &os, const std::multiset<T> &vec) { os << '{'; for (auto v : vec) os << v << ','; os << '}'; return os; }
template <class OStream, class T> OStream &operator<<(OStream &os, const std::unordered_multiset<T> &vec) { os << '{'; for (auto v : vec) os << v << ','; os << '}'; return os; }
template <class OStream, class T, class U> OStream &operator<<(OStream &os, const std::pair<T, U> &pa) { return os << '(' << pa.first << ',' << pa.second << ')'; }
template <class OStream, class TK, class TV> OStream &operator<<(OStream &os, const std::map<TK, TV> &mp) { os << '{'; for (auto v : mp) os << v.first << "=>" << v.second << ','; os << '}'; return os; }
template <class OStream, class TK, class TV, class TH> OStream &operator<<(OStream &os, const std::unordered_map<TK, TV, TH> &mp) { os << '{'; for (auto v : mp) os << v.first << "=>" << v.second << ','; os << '}'; return os; }
#ifdef HITONANODE_LOCAL
const string COLOR_RESET = "\033[0m", BRIGHT_GREEN = "\033[1;32m", BRIGHT_RED = "\033[1;31m", BRIGHT_CYAN = "\033[1;36m", NORMAL_CROSSED = "\033[0;9;37m", RED_BACKGROUND = "\033[1;41m", NORMAL_FAINT = "\033[0;2m";
#define dbg(x) std::cerr << BRIGHT_CYAN << #x << COLOR_RESET << " = " << (x) << NORMAL_FAINT << " (L" << __LINE__ << ") " << __FILE__ << COLOR_RESET << std::endl
#define dbgif(cond, x) ((cond) ? std::cerr << BRIGHT_CYAN << #x << COLOR_RESET << " = " << (x) << NORMAL_FAINT << " (L" << __LINE__ << ") " << __FILE__ << COLOR_RESET << std::endl : std::cerr)
#else
#define dbg(x) ((void)0)
#define dbgif(cond, x) ((void)0)
#endif

#include <atcoder/segtree>

struct S {
    lint n0 = 0;
    lint n1 = 0;
    lint v00 = 0;
    lint v01 = 0;
    lint v10 = 0;
    lint v11 = 0;
    lint v01e = 0;
    lint v11e = 0;
    lint n1e = 0;
    bool is_empty = false;
    // template <class OStream>
    // friend OStream &operator<<(OStream &os, const S &s) {
    //     return os << "S(" << s.n0 << ", " << s.n1 << ", " << s.v00 << ", " << s.v01 << ", " << s.v10 << ", " << s.v11 << ", " << s.n0e << ", " << s.n1e << ", " << (s.is_empty ? "true" : "false") << ")";
    // }
};

S op(S l, S r) {
    if (r.is_empty) return l;
    if (l.is_empty) return r;
    S res;
    res.n0 = r.n0 + l.n0 * r.v00 + l.n1 * r.v10;
    res.n1 = r.n1 + l.n0 * r.v01 + l.n1 * r.v11;
    res.v00 = l.v00 * r.v00 + l.v01 * r.v10;
    res.v01 = l.v00 * r.v01 + l.v01 * r.v11;
    res.v10 = l.v10 * r.v00 + l.v11 * r.v10;
    res.v11 = l.v10 * r.v01 + l.v11 * r.v11;
    // res.n0e = l.n0e + r.n0e + l.n0 * r.v00 + l.n1 * r.v10;
    res.v01e = l.v01e + l.v00 * r.v01e + l.v01 * r.v11e;
    res.v11e = l.v11e + l.v10 * r.v01e + l.v11 * r.v11e;
    res.n1e = l.n1e + r.n1e + l.n0 * r.v01e + l.n1 * r.v11e;
    res.is_empty = false;
    return res;
}

S e() { return {0, 0, 1, 0, 0, 1, 0, 0, 0, true}; }
S Gen(string c) {
    if (c == "F") return {1, 0, 0, 0, 0, 0, 0, 0, 0, false};
    if (c == "T") return {0, 1, 0, 0, 0, 0, 0, 0, 1, false};
    if (c == "+F") return {1, 0, 1, 0, 0, 1, 0, 1, 0, false};
    if (c == "+T") return {0, 1, 0, 1, 0, 1, 1, 1, 1, false};
    if (c == "*F") return {1, 0, 1, 0, 1, 0, 0, 0, 0, false};
    if (c == "*T") return {0, 1, 1, 0, 0, 1, 0, 1, 1, false};
    if (c == "^F") return {1, 0, 1, 0, 0, 1, 0, 1, 0, false};
    if (c == "^T") return {0, 1, 0, 1, 1, 0, 1, 0, 1, false};
    assert(false);
}

int main() {
    int N, Q;
    string X;
    cin >> N >> Q >> X;
    vector<S> init;
    for (int i = 1; i < N; i += 2) { init.push_back(Gen(X.substr(i, 2))); }

    const atcoder::segtree<S, op, e> seg(init);

    while (Q--) {
        int L, R;
        cin >> L >> R;
        --L;
        if (L % 2) ++L;
        if (R % 2 == 0) --R;
        dbg(make_tuple(L, R));
        if (L >= R) {
            cout << 0 << '\n';
        } else {
            const S a = Gen(X.substr(L, 1));
            const S m = seg.prod(L / 2, R / 2);
            auto o = op(a, m);
            dbg(make_tuple(L / 2, R / 2));
            // dbg(a);
            // dbg(m);
            // dbg(o);
            cout << o.n1e << '\n';
        }
    }
}