1 #include<iostream>
  2 #include<cstdio>
  3 #include<cstring>
  4 using namespace std;
  5 #define min(a,b) ((a)<(b)?(a):(b))
  6 #define qq 1e9
  7 int read() {
  8     int s=0,f=1;
  9     char ch=getchar();
 10     while(ch>‘9‘||ch<‘0‘) {
 11         if(ch==‘-‘) {
 12             f=-1;
 13         }
 14         ch=getchar();
 15     }
 16     while(ch>=‘0‘&&ch<=‘9‘) {
 17         s=(s<<1)+(s<<3)+(ch^48);
 18         ch=getchar();
 19     }
 20     return s*f;
 21 }
 22 int n,r[105],tot,deep[105],S,T;
 23 int head,tail,queue[105];
 24 struct oo {
 25     int to,vv,next;
 26 } c[10005];
 27 void add(int x,int y,int z) {
 28     c[tot].to=y;
 29     c[tot].next=r[x];
 30     c[tot].vv=z;
 31     r[x]=tot++;
 32 }
 33 bool bfs(int s,int t) {
 34     memset(deep,0,sizeof(deep));
 35     head=tail=0;
 36     queue[++tail]=s;
 37     deep[s]=1;
 38     while(head<tail) {
 39         int opt=queue[++head];
 40         for(int i=r[opt]; ~i; i=c[i].next) {
 41             if(c[i].vv&&!deep[c[i].to]) {
 42                 deep[c[i].to]=deep[opt]+1;
 43                 queue[++tail]=c[i].to;
 44                 if(c[i].to==t) {
 45                     return 1;
 46                 }
 47             }
 48         }
 49     }
 50     return 0;
 51 }
 52 int dfs(int opt,int fw) {
 53     if(opt==T) {
 54         return fw;
 55     }
 56     int tmp=fw,k;
 57     for(int i=r[opt]; ~i; i=c[i].next) {
 58         if(c[i].vv&&tmp&&deep[c[i].to]==deep[opt]+1) {
 59             k=dfs(c[i].to,min(c[i].vv,tmp));
 60             if(!k) {
 61                 deep[c[i].to]=0;
 62                 continue;
 63             }
 64             c[i].vv-=k;
 65             c[i^1].vv+=k;
 66             tmp-=k;
 67         }
 68     }
 69     return fw-tmp;
 70 }
 71 int dicnic(int s,int t){
 72     int ans=0;
 73     while(bfs(s,t)){
 74         ans+=dfs(s,qq);
 75     }
 76     return ans;
 77 }
 78 int n1;
 79 int Main(){
 80     freopen("flyer.in","r",stdin);
 81     freopen("flyer.out","w",stdout);
 82     scanf("%d%d",&n,&n1);
 83     T=n+1;
 84     memset(r,-1,sizeof(r));
 85     int a,b;
 86     for(int i=1;i<=n1;i++){
 87         add(S,i,1);
 88         add(i,S,0);
 89     }
 90     for(int i=n1+1;i<=n;i++){
 91         add(i,T,1);
 92         add(T,i,0);
 93     }
 94     while(scanf("%d%d",&a,&b)==2){
 95         add(a,b,1);
 96         add(b,a,0);
 97     }
 98     int ans=dicnic(S,T);
 99     printf("%d\n",ans);
100     return 0;
101 }
102 int hehe=Main();
103 int main() {
104     ;
105 }