#include <bits/stdc++.h>

using namespace std;

struct fenvik {
    int n;
    vector <int> t;
    fenvik() {}
    fenvik(int n) : n(n), t(vector <int> (n)) {}
    void add(int i, int val) {
        if (i < 0) return;
        while (i < n) {
            t[i] += val;
            i |= i + 1;
        }
        return;
    }
    int pref(int i) {
        int res = 0;
        while (i >= 0) {
            res += t[i];
            i = (i & (i + 1)) - 1;
        }
        return res;
    }
    int sum(int l, int r) {
        return pref(r) - pref(l - 1);
    }
};

const int N = 2e5 + 100, Q = 2e5 + 100;

int open[N], close[N], pref_black[Q], query[Q], addX[N], addY[N];

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    int n, q, added = 0;
    cin >> n >> q;
    fill_n(open, n, -1);
    fill_n(close, n, -1);
    for (int i = 0; i < q; i++) {
        string z;
        int t;
        cin >> z >> t; t--;
        query[i] = t;
        if (z == "add") {
            open[t] = i;
            added++;
        } else {
            close[t] = i;
        }
    }

    fenvik tree = fenvik(q), treeRed = fenvik(q);
    for (int i = 0; i < q; i++) {
        int t = query[i];
        if (open[t] == i && close[t] != -1) {
            addY[t] += pref_black[i];
        }
        if (close[t] == i) {
            addY[t] += tree.sum(0, open[t] - 1);
            addX[t] += treeRed.pref(open[t]);
        }

        pref_black[i + 1] = pref_black[i];
        if (open[t] == i && close[t] == -1) {
            pref_black[i + 1]++;
        }
        if (close[t] == i) {
            tree.add(open[t], -1);
            treeRed.add(i + 1, -1);
            treeRed.add(open[t], 1);
        }
        if (close[t] != -1 && open[t] == i) {
            tree.add(i, 1);
        }
    }

    long long ans = 0;
    for (int i = 0; i < n; i++) {
        if (close[i] != -1) ans += min(addX[i], addY[i]) * 2 + 1;
    }
    ans += added;
    cout << ans << '\n';
    return 0;
}
ф