#include <bits/stdc++.h>
using namespace std;
#define Joyfine ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define int long long
const int N=1e5+10;
int _=1;
int n,m;
vector<int> g[N];
int fa[N], siz[N], sz[N];
int sg[3];
int f[N][2];
int find(int x) {return x==fa[x]?x:fa[x]=find(fa[x]);}
void merge(int u, int v) {
    int fu = find(u);
    int fv = find(v);
    if (fu != fv) {
        fa[fv] = fu;
        siz[fu] += siz[fv];
    }
}
void DFS(int u, int fa) {
    for (auto v : g[u])
        if (v != fa) {
            DFS(v, u);
            sz[u] = sz[u] + sz[v];
        }
}
void dfs(int u, int fa) {
    if (fa != 0) {
        if ((siz[find(u)] - sz[u]) % 2)
            f[u][1]++;
        else
            f[u][0]++;
    }
    for (auto v : g[u])
        if (v != fa) {
            if (sz[v] % 2)
                f[u][1]++;
            else
                f[u][0]++;
                dfs(v, u)}
}
void solve(int ce) {
    sg[1] = 1;
    sg[0] = 2;
    int ans = 0;
    cin >> n >> m;
    for (int i = 1; i <= n; i++) fa[i] = i, siz[i] = 1, sz[i] = 1;
    for (int i = 1, u, v; i <= m; i++) {
        cin >> u >> v;
        merge(u, v);
        g[u].push_back(v);
        g[v].push_back(u);
    }
    vector<int> v;
    int sum = 0;
    for (int i = 1; i <= n; i++) {
        if (fa[i] == i) {
            v.push_back(siz[i]);
            sum ^= sg[siz[i] % 2];
        }
    }
    for (auto i : v) {
        if (sum == 2 && i % 2 == 0) {
            ans += (i - 1);
        } else if (sum == 2 && i % 2 == 1) {
            ans += (i - 1);
        }
    }
    for (int i = 1; i <= n; i++) {
        if (fa[i] == i) {
            DFS(i, 0);
            dfs(i, 0);
        }
    }
    for (int i = 1; i <= n; i++) {
        // cout << siz[i] << endl;
        int a1 = f[i][0] % 2, a2 = f[i][1] % 2;
        if ((sum ^ sg[siz[find(i)] % 2] ^ (2 * a1) ^ (a2)) == 0) {
            ans++;
        }
        // cout << f[i][0] << " " << f[i][1] << endl;
    }
    cout << ans;
}
signed main(void) 
{
    Joyfine;
    // cin>>_;
    for(int i=1;i<=_;i++) solve(i);
}

answer.code: In function ‘void dfs(long long int, long long int)’:
answer.code:41:26: error: expected ‘;’ before ‘}’ token
   41 |                 dfs(v, u)}
      |                          ^
      |                          ;