#pragma region templates
//C
#ifndef _GLIBCXX_NO_ASSERT
#include <cassert>
#endif
#include <cctype>
#include <cerrno>
#include <cfloat>
#include <ciso646>
#include <climits>
#include <clocale>
#include <cmath>
#include <csetjmp>
#include <csignal>
#include <cstdarg>
#include <cstddef>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>

#if __cplusplus >= 201103L
#include <ccomplex>
#include <cfenv>
#include <cinttypes>
#include <cstdalign>
#include <cstdbool>
#include <cstdint>
#include <ctgmath>
#include <cwchar>
#include <cwctype>
#endif

// C++
#include <algorithm>
#include <bitset>
#include <complex>
#include <deque>
#include <exception>
#include <fstream>
#include <functional>
#include <iomanip>
#include <ios>
#include <iosfwd>
#include <iostream>
#include <istream>
#include <iterator>
#include <limits>
#include <list>
#include <locale>
#include <map>
#include <memory>
#include <new>
#include <numeric>
#include <ostream>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <stdexcept>
#include <streambuf>
#include <string>
#include <typeinfo>
#include <utility>
#include <valarray>
#include <vector>

#if __cplusplus >= 201103L
#include <array>
#include <atomic>
#include <chrono>
#include <condition_variable>
#include <forward_list>
#include <future>
#include <initializer_list>
#include <mutex>
#include <random>
#include <ratio>
#include <regex>
#include <scoped_allocator>
#include <system_error>
#include <thread>
#include <tuple>
#include <typeindex>
#include <type_traits>
#include <unordered_map>
#include <unordered_set>
#endif

using i8  = std::int8_t;
using i16 = std::int16_t;
using i32 = std::int32_t;
using i64 = std::int64_t;
using u8  = std::uint8_t;
using u16 = std::uint16_t;
using u32 = std::uint32_t;
using u64 = std::uint64_t;
using f32 = float;
using f64 = double;
using vi32  = std::vector<i32>;
using vu32  = std::vector<u32>;
using vi64  = std::vector<i64>;
using vu64  = std::vector<u64>;
using vvi32 = std::vector<vi32>;
using vvu32 = std::vector<vu32>;
using vvi64 = std::vector<vi64>;
using vvu64 = std::vector<vu64>;
using pi32  = std::pair<i32,i32>;
using pi64  = std::pair<i64,i64>;

#define FOR(i,a,b) for(i64 i=(a), i##_len=(b); i<i##_len; ++i)
#define REP(i,n) FOR(i,0,n)
#define REPS(i,n) for(i64 i=1LL; i<=static_cast<i64>(n); ++i)
#define RFOR(i,a,b) for(i64 i=(a), i##_len=(b); i>i##_len; --i)
#define RFORS(i,n) RFOR(i,n,0)

#define ALL(obj) (obj).begin(),(obj).end()
#define CLR(ar,val) memset(ar, val, sizeof(ar))
#define SZ(obj) (static_cast<i32>(obj.size()))
#define cauto const auto&
#define pb push_back
#define mp make_pair

const i32 dx[4]={1,0,-1,0};
const i32 dy[4]={0,1,0,-1};
const i32 INF32 = 0x3F3F3F3F;
const i64 INF64 = 0x3F3F3F3F3F3F3F3F;

template<class T> inline bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T> inline bool chmin(T &a, const T &b) { if (b<a) { a=b; return 1; } return 0; }

class range {
private:
    struct I {
        i32 x;
        i32 operator*() { return x; }
        bool operator!=(I& lhs) { return x<lhs.x; }
        void operator++() { ++x; }
    };
    I i,n;
public:
    explicit range(int n) : i({0}), n({n}) { }
    range(int i,int n) : i({i}), n({n}) { }
    I& begin() { return i; }
    I& end() { return n; }
};

struct IoSetup {
    IoSetup() {
        std::cin.tie(nullptr);
        std::ios::sync_with_stdio(false);
        std::cout << std::fixed << std::setprecision(10);
        std::cerr << std::fixed << std::setprecision(10);
    }
}iosetup;/// cin,coutを使うときは iosetup をここにつける

template<typename A, typename B> std::istream &operator>>(std::istream &is, std::pair<A, B> &p) { is >> p.first >> p.second;return is; }
template<typename A, typename B> std::ostream &operator<<(std::ostream &os, const std::pair<A, B>& p) { os << p.first << ' ' << p.second;return os; }
template<typename T> std::istream &operator>>(std::istream &is, std::vector<T> &v) { for(T& in : v) is >> in; return is; }
template<typename T> std::ostream &operator<<(std::ostream &os, const std::vector<T> &v) { for(i32 i = 0; i < SZ(v); i++) os << v[i] << (i+1 != SZ(v) ? " " : ""); return os; }
#pragma endregion

struct RollingHash {
    using hash_type = std::pair<i64,i64>;

    i64 base1; i64 base2; i64 mod1; i64 mod2; vi64 hash1; vi64 hash2; vi64 pow1; vi64 pow2;

    RollingHash() : base1(1009), base2(1007), mod1(1000000007), mod2(1000000009) { }

    void init(const std::string& s) {
        i32 n = s.size();

        hash1.assign(n+1,0); hash2.assign(n+1,0); pow1.assign(n+1,1); pow2.assign(n+1,1);

        for(i32 i = 0; i < n; i++) {
            hash1[i+1] = (hash1[i]+s[i]) * base1 % mod1;
            hash2[i+1] = (hash2[i]+s[i]) * base2 % mod2;
            pow1[i+1] = pow1[i] * base1 % mod1;
            pow2[i+1] = pow2[i] * base2 % mod2;
        }
    }

    hash_type get(i32 l,i32 r) {
        i64 t1 = ((hash1[r] - hash1[l] * pow1[r-l]) % mod1 + mod1) % mod1;
        i64 t2 = ((hash2[r] - hash2[l] * pow2[r-l]) % mod2 + mod2) % mod2;
        return std::make_pair(t1, t2);
    }

    RollingHash::hash_type concat(hash_type h1, hash_type h2, i32 h2_len) {
        return std::make_pair((h1.first * pow1[h2_len] + h2.first) % mod1, (h1.second * pow2[h2_len] + h2.second) % mod2);
    }

};

i32 main () {
    using namespace std;

    i32 N, Q; cin >> N >> Q;
    string s; cin >> s;
    
    RollingHash rh;
    rh.init(s);
    
    i64 lv = 0, rv = 0;
    i64 ans = 0; 
    map<pi64, i64> mp;

    while (Q--) {
        string query; cin >> query;
        if (query == "R++") {
            rv++;
        } else if (query == "R--") {
            rv--;
        } else if (query == "L++") {
            lv++;
        } else if (query == "L--") {
            lv--;
        }
        auto d = rh.get(lv, rv+1);
        if (mp[d] == 0){
            ans++;
            mp[d]++;
        }
    }
    cout << ans << endl;
}


Measured memory_bytes: 31240