#include <bits/stdc++.h>
using namespace std;

const int MXN = 250005;
int N, M, head[MXN], to[MXN << 1], nxt[MXN << 1];
int dfn[MXN], low[MXN], did;
bool dep[MXN];
unsigned tag[MXN], val[MXN << 1], S;
mt19937 rnd(random_device{}());

void dfs(int p, int le) {
  low[p] = dfn[p] = did++;
  for (int e(head[p]); ~e; e = nxt[e]) {
    if (!(e ^ le ^ 1)) continue;
    int q(to[e]);
    if (~dfn[q]) {
      if (dfn[q] < dfn[p]) {
        unsigned v(rnd());
        val[e] = v, tag[p] ^= v, tag[q] ^= v;
        S ^= !(dep[p] ^ dep[q]) * v;
      }
    } else {
      dep[q] = !dep[p];
      dfs(q, e);
      low[p] = min(low[p], low[q]);
      val[e] = tag[q];
      tag[p] ^= tag[q];
    }
  }
}

int main() {
  cin >> N >> M;
  memset(head, -1, sizeof head);
  for (int i(0), x(0), y(0); i != M; ++i) {
    cin >> x >> y, --x, --y;
    to[i << 1] = y, nxt[i << 1] = head[x], head[x] = i << 1;
    to[i << 1 | 1] = x, nxt[i << 1 | 1] = head[y], head[y] = i << 1 | 1;
  }
  memset(dfn, -1, sizeof dfn);
  dfs(0, -1);
  if (!S) {
    cout << "1\n";
    return 0;
  }
  map<int, int> cnt;
  for (int i(0); i != M; ++i) ++cnt[val[i << 1] ^ val[i << 1 | 1]];
  if (cnt[S]) {
    cout << cnt[S] << endl;
  } else {
    long long sum(0);
    vector<pair<int, int>> vec(cnt.begin(), cnt.end());
    for (auto [p, q] : vec)
      sum += q * 1LL * cnt[S ^ p];
    cout << sum / 2 << endl;
  }
  return 0;
}