#include <bits/stdc++.h>

 using namespace std;

 const int maxn=+,INF=0x7fffffff;

 int n,m,cnt=;

 int lvl[maxn],itr[maxn],head[maxn];

 struct edge{

     int to,cap,next;

     edge(){}

     edge(int to,int cap,int next):to(to),cap(cap),next(next){}

 }g[maxn*maxn*];

 void add_edge(int u,int v,int cap){

     g[++cnt]=edge(v,cap,head[u]); head[u]=cnt;

     g[++cnt]=edge(u,,head[v]); head[v]=cnt;

 }

 void bfs(int s){

     memset(lvl,-,sizeof lvl);

     lvl[s]=;

     queue <int> q;

     q.push(s);

     while(!q.empty()){

         int u=q.front(); q.pop();

         for(int i=head[u];i;i=g[i].next){

             int v=g[i].to;

             if(lvl[v]<&&g[i].cap>){

                 lvl[v]=lvl[u]+;

                 q.push(v);

             }

         }

     }

 }

 int dfs(int u,int t,int f){

     if(u==t) return f;

     for(int &i=itr[u];i;i=g[i].next){

         int v=g[i].to;

         if(g[i].cap>&&lvl[u]<lvl[v]){

             int d=dfs(v,t,min(f,g[i].cap));

             if(d>){

                 g[i].cap-=d;

                 g[i^].cap+=d;

                 return d;

             }

         }

     }

     return ;

 }

 int max_flow(int s,int t){

     int flow=;

     for(bfs(s);lvl[t]>;bfs(s)){

         for(int i=;i<=n+;i++) itr[i]=head[i];

         int f;

         while((f=dfs(s,t,INF))>) flow+=f;

     }

     return flow;

 }

 void init(){

     scanf("%d%d",&n,&m);

     for(int i=;i<=m;i++) add_edge(,i,);

     for(int i=m+;i<=n;i++) add_edge(i,n+,);

     int u,v;

     while(scanf("%d%d",&u,&v)!=EOF) add_edge(u,v,);

 }

 int main(){

     freopen("flyer.in","r",stdin);

     freopen("flyer.out","w",stdout);

     init();

     printf("%d\n",max_flow(,n+));

     fclose(stdin);

     fclose(stdout);

     return ;

 }