1 #include <bits/stdc++.h>
 2 using namespace std;
 3 const int maxn = 100010;
 4 int uf[maxn],d[maxn],odd[maxn];
 5 bool vis[maxn];
 6 int Find(int x){
 7     if(x != uf[x]) uf[x] = Find(uf[x]);
 8     return uf[x];
 9 }
10 vector<int>root;
11 int main(){
12     int n,m,u,v;
13     while(~scanf("%d%d",&n,&m)){
14         for(int i = 0; i < maxn; ++i){
15             uf[i] = i;
16             odd[i] = d[i] = 0;
17             vis[i] = false;
18         }
19         root.clear();
20         for(int i = 0; i < m; ++i){
21             scanf("%d%d",&u,&v);
22             ++d[u];
23             ++d[v];
24             u = Find(u);
25             v = Find(v);
26             if(u != v) uf[v] = u;
27         }
28         for(int i = 1; i <= n; ++i){
29             u = Find(i);
30             if(!vis[u]){
31                 vis[u] = true;
32                 root.push_back(u);
33             }
34             if(d[i]&1) ++odd[u];
35         }
36         int ret = 0;
37         for(int i = 0; i < root.size(); ++i){
38             if(!d[root[i]]) continue;
39             if(odd[root[i]] == 0) ret++;
40             else ret += odd[root[i]]/2;
41         }
42         printf("%d\n",ret);
43     }
44     return 0;
45 }