#include <bits/stdc++.h>
#define ll long long
using namespace std;
const ll INF = 1e18;
int n, q;
ll m1, m2, L, R, mid;
ll mid1, mid2;
int main(){
ios_base::sync_with_stdio(0); cin.tie(0);
cin >> n >> q;
if (!(n & 1)) mid1 = INF, mid2 = -INF;
while (q--){
char S; cin >> S;
int x; cin >> x;
if (S == 'D') {
m1 += x; m2 += x; mid2 += x;
if (x == n) ++L, ++R, ++mid1;
}
if (S == 'L') {
m1 += x;
L += max(x - (n >> 1) + 1, 0);
}
if (S == 'R') {
m2 += x;
R += max((n >> 1) + (n & 1 ? 2 : 1) - n + x, 0);
}
if ((n & 1) && (S == 'L' || S == 'R') && x == ((n + 1) >> 1))
++mid1, ++mid2;
}
cout << max({m1, m2, mid2}) - min({L, R, mid1});
// cout << "\n";
// cout << m1 << " " << m2 << " " << mid2 << "\t" << L << " " << R << " " << mid1 << "\n";
}
