#include <iostream>
#include <vector>
#include <algorithm>
#include <set>
using namespace std;
typedef long long int lli;
const lli mod1 = 1e9 +7, mod2 = 1e9+21;
const lli base1 = 1007, base2 = 1021;

lli power(lli n, lli p, lli mod){
	lli ret=1;
	for(int i=62; i>=0; i--){
		ret = (ret*ret)%mod;
		if((1LL<<i & p) != 0) ret = (ret*n)%mod;
	}
	return ret;
}

int main(){
	int n,m;
	string s;
	cin >> n >> m >> s;
	
	vector<lli> h1(n+1, 0), h2(n+1, 0);
	for(int i=0; i<n; i++){
		h1[i+1] = (h1[i]*base1 + s[i]-'a'+1)%mod1;
		h2[i+1] = (h2[i]*base2 + s[i]-'a'+1)%mod2;
	}
	int l=0, r=1;
	set<lli> sset1, sset2;
	int ans = 0;
	for(int i=0; i<m; i++){
		string q;
		cin >> q;
		if(q=="L++") l++;
		if(q=="L--") l--;
		if(q=="R++") r++;
		if(q=="R--") r--;
		lli hash1 = (h1[r] -(h1[l]*power(base1, r-l, mod1))%mod1 +mod1)%mod1;
		lli hash2 = (h2[r] -(h2[l]*power(base2, r-l, mod2))%mod2 +mod2)%mod2;
		if(sset1.find(hash1)==sset1.end() || sset2.find(hash2)==sset2.end()){
			ans++;
		}
		sset1.insert(hash1);
		sset2.insert(hash2);
	}
	cout << ans << endl;
	return 0;
}
