#include<iostream> #include<algorithm> #include<cstring> using namespace std; int g[1010][15];//pingweidetaidu int piao[15]; bool st[15];//the tip of pinpais bool success=true; int lastpiaoshu; int lastpinpai; int m,n; void pingxuan(){ while(1){ memset(piao,0,sizeof(piao));//chushihua for(int i=1;i<=n;i++){ for(int j=1;j<=n;j++){ int k=g[i][j]; if(k==0)break; if(st[k])continue;//品牌被淘汰 piao[k] ++; break; } } int maxn=-1001,minn=1001; for(int i=1;i<=m;i++){ if(piao[i]<minn&&!st[i])minn=piao[i]; if(piao[i]>maxn&&!st[i])maxn=piao[i]; } if(maxn>minn){ for(int i=1;i<=m;i++){ if(piao[i]==minn&&st[i]==false)st[i]=true; } continue; } else{ int sum=0; for(int i=1;i<=m;i++){ if(piao[i]==minn)sum++,lastpinpai=i; } if(sum==1)return; else{ lastpiaoshu=minn; success=false; return; } } } } int main() { cin>>m>>n; for(int i=1;i<=n;i++){ string str; cin>>str; for(int j=0;j<str.size();j++){ g[i][j+1]=str[j]-'0'; } } pingxuan(); if(success)cout<<lastpinpai<<endl; else cout<<"-"<<lastpiaoshu<<endl; return 0; }