#include<stdio.h>
//#include<bits/stdc++.h>
#include<string.h>
#include<iostream>
#include<math.h>
#include<sstream>
#include<set>
#include<queue>
//#include<map>
#include<vector>
#include<algorithm>
#include<limits.h>
#define inf 0x3fffffff
#define INF 0x3f3f3f3f
#define lson l,m,rt<<1
#define rson m+1,r,rt<<1|1
#define LL long long
#define ULL unsigned long long
using namespace std;
int map[110][110];
int dis[110];
int flag[110];
int n;
int Prime()
{
    int i,j;
    int pos,sum=0;
    memset(flag,0,sizeof(flag));
    for(i=1; i<=n; i++)
    {
        dis[i]=map[1][i];
    }
    flag[1]=1;
    for(i=1; i<n; i++)
    {
        int mid=inf;
        for(j=1; j<=n; j++)
        {
            if(!flag[j]&&dis[j]<mid)
            {
                mid=dis[j];
                pos=j;
            }
        }
        flag[pos]=1;
        sum+=mid;
        for(j=1; j<=n; j++)
        {
            if(!flag[j]&&map[pos][j]<dis[j])
            {
                dis[j]=map[pos][j];
            }
        }
    }
    return sum;
}
int main()
{
    int i,j;
    int q,a,b;
    while(~scanf("%d",&n))
    {
        memset(map,0,sizeof(map));
        int ans;
        for(i=1; i<=n; i++)
        {
            for(j=1; j<=n; j++)
            {
                scanf("%d",&ans);
                map[i][j]=-ans;
            }
        }
        printf("%d\n",-Prime());
    }
    return 0;
}