#include <iostream>
#include <cstdio>
#include <cmath>
#include <ctime>
#include <cstdlib>
#include <cassert>
#include <vector>
#include <list>
#include <stack>
#include <queue>
#include <deque>
#include <map>
#include <set>
#include <bitset>
#include <string>
#include <algorithm>
#include <utility>
#define llint long long
#define inf 1e18
#define rep(x, s, t) for(llint (x) = (s); (x) < (t); (x)++)
#define Rep(x, s, t) for(llint (x) = (s); (x) <= (t); (x)++)
#define chmin(x, y) (x) = min((x), (y))
#define chmax(x, y) (x) = max((x), (y))
#define mod 998244353

using namespace std;
typedef pair<llint, llint> P;

llint n, m;
map<llint, llint> mp, mp2;
vector<llint> G[400005], revG[400005];
vector<llint> g[400005];
vector<int> topo;
bool used[400005];
int scc[400005];
llint dp[400005];

void tpsort(int v)
{
	used[v] = true;
	for(int i = 0; i < G[v].size(); i++){
		if(!used[G[v][i]]) tpsort(G[v][i]);
	}
	topo.push_back(v);
}
void sccdfs(int v, int id)
{
	used[v] = true;
	scc[v] = id;
	for(int i = 0; i < revG[v].size(); i++){
		if(!used[revG[v][i]]) sccdfs(revG[v][i], id);
	}
}

int main(void)
{
	ios::sync_with_stdio(0);
	cin.tie(0);

	cin >> n >> m;
	llint u, v, id = 0;
	for(int i = 1; i <= m; i++){
		cin >> u >> v;
		if(mp.count(u) == 0){
			mp[u] = ++id;
			mp2[id] = u;
		}
		if(mp.count(v) == 0){
			mp[v] = ++id;
			mp2[id] = v;
		}
		G[mp[u]].push_back(mp[v]);
		revG[mp[v]].push_back(mp[u]);
	}
	llint N = id;
	
	for(int i = 1; i <= N; i++) if(!used[i]) tpsort(i);
	reverse(topo.begin(), topo.end());
	
	id = 0;
	for(int i = 1; i <= N; i++) used[i] = false;
	for(int i = 0; i < topo.size(); i++) if(!used[topo[i]]) sccdfs(topo[i], ++id);
	
	for(int i = 1; i <= N; i++){
		chmax(dp[scc[i]], mp2[i]);
		for(int j = 0; j < G[i].size(); j++){
			llint v = G[i][j];
			if(scc[v] != scc[i]) g[scc[i]].push_back(scc[v]);
		}
	}
	
	for(int i = id; i >= 1; i--){
		for(int j = 0; j < g[i].size(); j++){
			chmax(dp[i], dp[g[i][j]]);
		}
	}
	
	llint ans = n * (n+1) / 2;
	for(auto it = mp.begin(); it != mp.end(); it++){
		ans += dp[scc[it->second]] - it->first;
	}
	cout << ans << endl;
	
	return 0;
}