#include <cstdio>

#include <cstring>

#include <queue>

#include <set>

#include <map>

#include <stack>

#include <cstdlib>

#include <algorithm>

#include <vector>

#include <cmath>

using namespace std;

typedef long long LL;

typedef pair<int,int>pii;

const int N=8e2+;

const int INF=0x3f3f3f3f;

struct Node{

  int u,v,w;

  bool operator<(const Node &rhs)const{

    return w<rhs.w;

  }

}p[N*N];

int tot,n,w,fa[N];

int find(int x){

  return x==fa[x]?x:fa[x]=find(fa[x]);

}

int main(){

    while(~scanf("%d",&n)){

        tot=;

     for(int i=;i<=n;++i){

      fa[i]=i;

      for(int j=;j<=n;++j){

        scanf("%d",&w);

        if(i<j){++tot,p[tot].u=i,p[tot].v=j,p[tot].w=w;}

      }

    }

      sort(p+,p++tot);

      int ans=;

      for(int i=;i<=tot;++i){

        int u=find(p[i].u),v=find(p[i].v);

        if(u!=v){

          fa[u]=v;

          ans=p[i].w;

        }

      }

      printf("%d\n",ans);

    }

    return ;

}