#include <cstdio>#include <vector >using namespace std;const int maxn=1001;vector<int >G[maxn];int low[maxn],dfn[maxn];bool vis[maxn];int dg[maxn];int  dep,cnt;void dfs(int s,int f){    low[s]=dfn[s]=++dep;    vis[s]=true;    for(int i=0;i<G[s].size();i++){        int t=G[s][i];        if(t==f)continue;        if(!vis[t]){            dfs(t,s);            low[s]=min(low[s],low[t]);        }        else low[s]=min(low[s],dfn[t]);    }}int n,r;int main(){    scanf("%d%d",&n,&r);    int f,t;    while(r--){scanf("%d%d",&f,&t);G[f].push_back(t);G[t].push_back(f);}    dfs(1,-1);    for(int i=1;i<=n;i++){        for(int j=0;j<G[i].size();j++){            if(low[i]!=low[G[i][j]])dg[low[i]]++;        }    }    int ans=0;    for(int i=1;i<=n;i++){        if(dg[i]==1)ans++;    }    ans=(ans+1)/2;    printf("%d\n",ans);    return 0;}