#include <algorithm>
#include <bitset>
#include <cctype>
#include <cerrno>
#include <clocale>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <deque>
#include <exception>
#include <fstream>
#include <functional>
#include <limits>
#include <list>
#include <map>
#include <iomanip>
#include <ios>
#include <iosfwd>
#include <iostream>
#include <istream>
#include <ostream>
#include <queue>
#include <set>
#include <sstream>
#include <stdexcept>
#include <streambuf>
#include <string>
#include <utility>
#include <vector>
#include <cwchar>
#include <cwctype>
#include <stack>
#include <limits.h>
using namespace std;
const int inf = 2e9;
#define MAXN 55int i,n,m,s,t,ans,S,T,tot;
int head[MAXN << 1],depth[MAXN << 1],u[MAXN * MAXN],v[MAXN * MAXN];
bool g[MAXN][MAXN];struct edge
{int to,w,nxt;
} e[MAXN * MAXN * 2];inline void addedge(int u,int v,int w)
{tot++;e[tot] = (edge){v,w,head[u]};head[u] = tot;tot++;e[tot] = (edge){u,0,head[v]};head[v] = tot;
}
inline bool bfs()
{int i,l,r,u,v,w;static int q[MAXN << 1];memset(depth,0,sizeof(depth));q[l = r = 1] = S;depth[S] = 1;while (l <= r){u = q[l];l++;for (i = head[u]; i; i = e[i].nxt){v = e[i].to;w = e[i].w;if (!depth[v] && w){depth[v] = depth[u] + 1;q[++r] = v;if (v == T) return true;}}}return false;
}
inline int dinic(int u,int flow)
{int i,v,w,k,rest = flow;if (u == T) return flow;for (i = head[u]; i && rest; i = e[i].nxt){v = e[i].to;w = e[i].w;if (depth[v] == depth[u] + 1 && w){k = dinic(v,min(rest,w));if (!k) depth[v] = 0;e[i].w -= k;e[i ^ 1].w += k;rest -= k;}}return flow - rest;
}
inline int getans(int s,int t)
{int i,Minimum_Cut,flow;tot = 1;memset(head,0,sizeof(head));for (i = 0; i < n; i++) {if (i != s && i != t)addedge(i,i + n,1);else addedge(i,i + n,inf);}for (i = 1; i <= m; i++){addedge(u[i] + n,v[i],inf);addedge(v[i] + n,u[i],inf);        } Minimum_Cut = 0;S = s;T = t;while (bfs()){while (flow = dinic(S,inf)) Minimum_Cut += flow;}return Minimum_Cut;
}int main()
{while (scanf("%d%d",&n,&m) != EOF){ans = inf;memset(g,false,sizeof(g));for (i = 1; i <= m; i++) {scanf(" (%d,%d)",&u[i],&v[i]);g[u[i]][v[i]] = g[v[i]][u[i]] = true;}for (s = 0; s < n; s++)        {for (t = 0; t < n; t++){if (!g[s][t] && s != t) ans = min(ans,getans(s,t));}}if (n <= 1 || ans == inf) ans = n;printf("%d\n",ans);}return 0;}