#include <bits/stdc++.h>

using namespace std;

const int maxC = (int) 1e9 + 1;

struct Node {
    int val, add;
    Node *l, *r;

    Node() : val(0), add(0), l(nullptr), r(nullptr) {};
};

void createSon(Node *v) {
    if (v->l == nullptr)
        v->l = new Node();
    if (v->r == nullptr)
        v->r = new Node();
}

void push(Node *v, int l, int r) {
    if (v->add == 0) return;
    v->val += v->add * (r - l + 1);
    if (l != r) {
        createSon(v);
        v->l->add += v->add, v->r->add += v->add;
    }
    v->add = 0;
}

void update(Node *v, int l, int r, int tl, int tr, int add) {
    push(v, l, r);
    if (l > tr || r < tl)
        return;
    if (l >= tl && r <= tr) {
        v->add += add;
        push(v, l, r);
        return;
    }
    int mid = (l + r) / 2;
    createSon(v);
    update(v->l, l, mid, tl, tr, add);
    update(v->r, mid + 1, r, tl, tr, add);
    v->val = v->l->val + v->r->val;
}

int get_sum(Node *v, int l, int r, int tl, int tr) {
    push(v, l, r);
    if (l > tr || r < tl)
        return 0;
    if (l >= tl && r <= tr)
        return v->val;
    int mid = (l + r) / 2;
    createSon(v);
    return get_sum(v->l, l, mid, tl, tr)
           + get_sum(v->r, mid + 1, r, tl, tr);
}

void Add(Node *v, int x) {
    update(v, 0, maxC, 1, x, -1);
    update(v, 0, maxC, 0, 0, x);
    update(v, 0, maxC, x + 1, maxC, 1);
}

void Del(Node *v, int x) {
    update(v, 0, maxC, 1, x - 1, 1);
    update(v, 0, maxC, 0, 0, -x);
    update(v, 0, maxC, x + 1, maxC, -1);
}

int get(Node *v, int x) {
    return get_sum(v, 0, maxC, 0, x);
}

Node *r1 = new Node(), *r2 = new Node();

int find_ans(Node *v) {
    int l = 0, r = maxC;
    while (r - l > 1) {
        int mid = (l + r) / 2;
        if (get(v, mid) <= get(v, mid - 1)) l = mid;
        else r = mid;
    }
    return get(v, l);
}

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr), cout.tie(nullptr);
    int k, n, add = 0;
    cin >> k >> n;
    vector<int> s, t;
    for (int i = 0; i < n; i++) {
        char p, q;
        int S, T;
        cin >> p >> S >> q >> T;
        if (S < T) swap(S, T);
        if (p == q) {
            add += S - T;
        } else {
            s.emplace_back(S), t.emplace_back(T);
        }
    }
    n = (int) s.size();
    if (n == 0) {
        cout << add;
        return 0;
    }
    if (k == 1) {
        for (int i = 0; i < n; i++)
            Add(r1, s[i]), Add(r1, t[i]);
        cout << find_ans(r1) + add + n;
        return 0;
    }
    return 0;
}