#include<bits/stdc++.h>
#define all(x) begin(x), end(x)
using namespace std;
using ll = long long;
struct DSU {
    vector<int> e;
    DSU(int n) : e(n, -1) {}
    int find(int v) { return e[v] < 0 ? v : e[v] = find(e[v]); }
    bool join(int u, int v) {
        u = find(u), v = find(v);
        if(u == v) return 0;
        if(-e[u] < -e[v]) swap(u, v);
        e[u] += e[v];
        e[v] = u;
        return 1;
    }
};
int main() {
    cin.tie(0)->sync_with_stdio(0);
    int n, m;
    cin >> n >> m;
    vector<vector<int>> g(n);
    for(int u, v, i = 0; i < m; i++) {
        cin >> u >> v;
        g[--u].push_back(--v);
        g[v].push_back(u);
    }
    vector<int> vis(n);
    int even, sz;
    auto dfs = [&](auto self, int v, int p) -> void {
        vis[v] = 1;
        sz++;
        even += g[v].size() % 2 == 0;
        for(auto i : g[v]) if(i ^ p) {
            self(self, i, v);
        }
    };
    int val = 0, ans = 0;
    for(int i = 0; i < n; i++) 
        if(!vis[i]) {
            even = 0, sz = 0, dfs(dfs, i, i);
            if(sz % 2 == 0) {
                val ^= 2;
                ans += sz - 1;
            } else {
                val ^= 1;
                ans += even;
            }
        }
    if(!val) ans = 0;
    cout << ans << '\n';
}