#include <bits/stdc++.h>
using namespace std;
const double PI = acos(-1);
const double eps = 1e-9;
const int inf = 2000000000;
const long long infLL = 9000000000000000000;
inline bool checkBit(long long n, int i) { return n & (1LL << i); }
inline long long setBit(long long n, int i) {
  return n | (1LL << i);
  ;
}
inline long long resetBit(long long n, int i) { return n & (~(1LL << i)); }
int dx[] = {0, 0, +1, -1};
int dy[] = {+1, -1, 0, 0};
inline bool EQ(double a, double b) { return fabs(a - b) < 1e-9; }
inline bool isLeapYear(long long year) {
  return (year % 400 == 0) || (year % 4 == 0 && year % 100 != 0);
}
inline void normal(long long &a) {
  a %= 1000000007;
  (a < 0) && (a += 1000000007);
}
inline long long modMul(long long a, long long b) {
  a %= 1000000007, b %= 1000000007;
  normal(a), normal(b);
  return (a * b) % 1000000007;
}
inline long long modAdd(long long a, long long b) {
  a %= 1000000007, b %= 1000000007;
  normal(a), normal(b);
  return (a + b) % 1000000007;
}
inline long long modSub(long long a, long long b) {
  a %= 1000000007, b %= 1000000007;
  normal(a), normal(b);
  a -= b;
  normal(a);
  return a;
}
inline long long modPow(long long b, long long p) {
  long long r = 1;
  while (p) {
    if (p & 1) r = modMul(r, b);
    b = modMul(b, b);
    p >>= 1;
  }
  return r;
}
inline long long modInverse(long long a) { return modPow(a, 1000000007 - 2); }
inline long long modDiv(long long a, long long b) {
  return modMul(a, modInverse(b));
}
const int maxn = 1010000;
struct Hash {
  long long val1 = 0, val2 = 0;
  long long base1 = 1827017, base2 = 5195977;
  long long mod1 = 100888001, mod2 = 133767331;
  void push(int num) {
    val1 *= base1;
    val1 += num;
    val1 %= mod1;
    val2 *= base2;
    val2 += num;
    val2 %= mod2;
  }
  bool operator<(const Hash &p) const {
    if (val1 == p.val1) return val2 < p.val2;
    return val1 < p.val1;
  }
  bool operator==(const Hash &p) const {
    return val1 == p.val1 && val2 == p.val2;
  }
};
map<Hash, int> cnt;
set<int> adjList[maxn];
int a[maxn], b[maxn];
vector<Hash> store;
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  ;
  int n, m;
  cin >> n >> m;
  store.resize(n + 1);
  for (int i = 0; i < m; ++i) {
    int u, v;
    cin >> u >> v;
    adjList[u].insert(v);
    adjList[v].insert(u);
    a[i] = u;
    b[i] = v;
  }
  for (int i = 1; i <= n; ++i) {
    Hash temp;
    for (auto it : adjList[i]) temp.push(it);
    cnt[temp]++;
  }
  long long ans = 0LL;
  for (auto it : cnt)
    ans += ((long long)(it.second) * (long long)(it.second - 1)) / 2;
  for (int i = 1; i <= n; ++i) {
    adjList[i].insert(i);
    for (auto it : adjList[i]) store[i].push(it);
  }
  for (int i = 0; i < m; ++i)
    if (store[a[i]] == store[b[i]]) ++ans;
  cout << ans;
  return 0;
}
