H

#include <bits/stdc++.h>
// tiom4eg's precompiler options
// POGGERS POGGERS POGGERS POGGERS POGGERS POGGERS POGGERS
// IO settings
#define fastIO ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0)
// Quick types
#define ll long long
#define ull unsigned long long
#define pii pair <int, int>
#define vi vector <int>
#define mi vector <vector <int> >
// Quick functions
#define endl "\n"
#define F first
#define S second
#define all(a) a.begin(), a.end()
#define pb push_back
#define fint(n) int n; cin >> n
#define fstr(s) string s; cin >> s
#define farr(a, n) int a[n]; for (int pog = 0; pog < n; ++pog) cin >> a[pog]
// Quick fors
#define FOR1(s, n) for (int i = s; i < n; ++i)
#define FOR2(s, n) for (int j = s; j < n; ++j)
#define FOR3(s, n) for (int k = s; k < n; ++k)
#define RFOR(n, s) for (int l = n; l >= s; --l)
// Pragmas
#pragma GCC optimize("Ofast")
// POGGERS POGGERS POGGERS POGGERS POGGERS POGGERS POGGERS
using namespace std;

ll n, m, res, h[1000000], g[2000000];

int main() {
    cin >> n >> m;
    h[0] = 1; g[n] = 1;
    FOR1(1, n) {
        h[i] = h[i - 1] * 1000000007;
        g[i + n] = h[i];
    }
    FOR1(0, m) {
        int a, b; cin >> a >> b;
        g[a - 1] += h[b - 1];
        g[a - 1 + n] += h[b - 1];
        g[b - 1] += h[a - 1];
        g[b - 1 + n] += h[a - 1];
    }
    sort(g, g + 2 * n);
    for (ll i = 0; i < 2 * n;) {
        ll j = i;
        while (g[j] == g[i]) i++;
        res += (i - j) * (i - j - 1) / 2;
    }
    cout << res;
}