#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL
string to_string(string s) { return '"' + s + '"'; }
string to_string(const char* s) { return to_string(string(s)); }
string to_string(bool b) { return to_string(int(b)); }
string to_string(char b) { return "'" + string(1, b) + "'"; }
template <typename A, typename B>
string to_string(pair<A, B> p) { return "(" + to_string(p.first) + ", " + to_string(p.second) + ")"; }
template <typename A>
string to_string(A v) {
	string res = "{";
	for (const auto& x : v) res += (res == "{" ? "" : ", ") + to_string(x);
	return res + "}";
}
void debug() { cerr << endl; }
template <typename Head, typename... Tail>
void debug(Head H, Tail... T) {
	cerr << " " << to_string(H);
	debug(T...);
}
#define db(...) cerr << "[" << #__VA_ARGS__ << "]:", debug(__VA_ARGS__)
#else
#define db(...) 42
#endif
typedef long long ll;
typedef long double ld;
int n;
struct SegTree {
	struct Node {
		ll x; // Set default value here
		ll prop = LLONG_MAX;
		// Used for updates and propagation.
		void apply(int s, int e, ll v) {
			x = min(x, v);
			prop = min(prop, v);
		}
	};
	inline Node combine(const Node& a, const Node& b) {
		Node res;
		res.x = min(a.x, b.x);
		return res;
	}
	inline void push(int sn, int s, int e) {
		if (tree[sn].prop != LLONG_MAX) {
			int m = (s + e) >> 1, lsn = sn * 2, rsn = sn * 2 + 1;
			tree[lsn].apply(s, m, tree[sn].prop);
			tree[rsn].apply(m + 1, e, tree[sn].prop);
			tree[sn].prop = LLONG_MAX;
		}
	}
	int start, end;
	vector<Node> tree;
	void build(int sn, int s, int e) {
		if (s == e) {
			// initialize here, possibly.
			tree[sn].x = n;
			return;
		}
		int m = (s + e) >> 1, lsn = sn * 2, rsn = sn * 2 + 1;
		build(lsn, s, m);
		build(rsn, m + 1, e);
		tree[sn] = combine(tree[lsn], tree[rsn]);
	}
	template <typename T>
	void build(int sn, int s, int e, const vector<T>& v) {
		if (s == e) {
			tree[sn].x = v[s];
			return;
		}
		int m = (s + e) >> 1, lsn = sn * 2, rsn = sn * 2 + 1;
		build(lsn, s, m, v);
		build(rsn, m + 1, e, v);
		tree[sn] = combine(tree[lsn], tree[rsn]);
	}
	template <typename... T>
	void update(int sn, int s, int e, int qs, int qe, const T&... v) {
		if (qs <= s && e <= qe) {
			tree[sn].apply(s, e, v...);
			return;
		}
		int m = (s + e) >> 1, lsn = sn * 2, rsn = sn * 2 + 1;
		push(sn, s, e);
		if (qs <= m) update(lsn, s, m, qs, qe, v...);
		if (qe > m) update(rsn, m + 1, e, qs, qe, v...);
		tree[sn] = combine(tree[lsn], tree[rsn]);
	}
	Node query(int sn, int s, int e, int qs, int qe) {
		if (qs <= s && e <= qe) return tree[sn];
		int m = (s + e) >> 1, lsn = sn * 2, rsn = sn * 2 + 1;
		push(sn, s, e);
		if (qe <= m) return query(lsn, s, m, qs, qe);
		if (qs > m) return query(rsn, m + 1, e, qs, qe);
		return combine(query(lsn, s, m, qs, qe), query(rsn, m + 1, e, qs, qe));
	}
	void query(int sn, int s, int e, int qs, int qe, const function<void(Node&, int, int)>& f) {
		if (qs <= s && e <= qe) return f(tree[sn], s, e);
		int m = (s + e) >> 1, lsn = sn * 2, rsn = sn * 2 + 1;
		push(sn, s, e);
		if (qs <= m) query(lsn, s, m, qs, qe, f);
		if (qe > m) query(rsn, m + 1, e, qs, qe, f);
	}
	SegTree(int n) : SegTree(0, n - 1) {}
	SegTree(int _start, int _end) : start(_start), end(_end) {
		int n = end - start + 1;
		int maxs = n == 1 ? 2 : 1 << (33 - __builtin_clz(n - 1));
		tree.resize(maxs);
		build(1, start, end);
	}
	template <typename T>
	SegTree(const vector<T>& v) {
		int n = v.size();
		int maxs = n == 1 ? 2 : 1 << (33 - __builtin_clz(n - 1));
		tree.resize(maxs);
		start = 0;
		end = n - 1;
		build(1, start, end, v);
	}
	Node query(int qs, int qe) {
		return query(1, start, end, qs, qe);
	}
	Node query(int p) {
		return query(1, start, end, p, p);
	}
	void query(int qs, int qe, const function<void(Node&, int, int)>& f) {
		if (qs > qe) return;
		query(1, start, end, qs, qe, f);
	}
	template <typename... T>
	void update(int qs, int qe, const T&... v) {
		update(1, start, end, qs, qe, v...);
	}
};
int main() {
	int q;
	scanf("%d%d", &n, &q);
	SegTree rst(n), cst(n);
	ll ans = (ll)(n - 2) * (n - 2);
	while (q--) {
		int t, x;
		scanf("%d%d", &t, &x);
		if (t == 1) {
			int firstWhite = cst.query(x).x;
			assert(firstWhite >= 2);
			ans -= firstWhite - 2;
			db(firstWhite, t, x);
			if (firstWhite > 2) {
				rst.update(2, firstWhite - 1, x);
			}
		} else {
			int firstWhite = rst.query(x).x;
			assert(firstWhite >= 2);
			ans -= firstWhite - 2;
			db(firstWhite, t, x);
			if (firstWhite > 2) {
				cst.update(2, firstWhite - 1, x);
			}
		}
	}
	printf("%lld\n", ans);
}


Measured memory_bytes: 19652