#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define mod 1000000007
#define esp 0.00000000001
const int N=1e5+10,M=1e6+10,inf=1e9;
const ll INF=1e18+10;
int n,m;
int fa[N],du[N],flag[N],mark[N],hh[N];
int Find(int x)
{
    return fa[x]==x?x:fa[x]=Find(fa[x]);
}
void update(int u,int v)
{
    int x=Find(u);
    int y=Find(v);
    if(x!=y)
    {
        fa[x]=y;
    }
}
void init()
{
    for(int i=0;i<N;i++)
        fa[i]=i;
    memset(flag,0,sizeof(flag));
    memset(du,0,sizeof(du));
    memset(mark,0,sizeof(mark));
    memset(hh,0,sizeof(hh));
}
int main()
{
    while(~scanf("%d%d",&n,&m))
    {
        init();
        for(int i=1;i<=m;i++)
        {
            int u,v;
            scanf("%d%d",&u,&v);
            update(u,v);
            du[u]++;
            du[v]++;
            hh[u]=1;
            hh[v]=1;
        }
        int ans=0,sum=0;
        for(int i=1;i<=n;i++)
        {
            if(!hh[i])continue;
            int x=Find(i);
            du[i]%=2;
            sum+=du[i];
            if(!flag[x])
            {
                ans++;
                flag[x]=1;
            }
            if(du[i]==1&&flag[x]&&!mark[x])
            {
                ans--;
                mark[x]=1;
            }
        }
        printf("%d\n",ans+sum/2);
    }
    return 0;
}