#include <stdio.h>
#include <string.h>
#define N 100+10
#define INF 9999999
int road[N][N];
int city[N];
int s[N];
int main()
{
	int i,j,n,rec,max,sum;

	while(scanf("%d",&n)!=EOF)
	{
		for(i=1;i<=n;i++)
	{
		getchar();
		for(j=1;j<=n;j++)
			scanf("%d",&road[i][j]);
	}
	memset(s,0,sizeof(s));
	for(i=1;i<=n;i++)
	city[i]=road[1][i];
	s[1]=1;
	sum=0;
	for(i=1;i<n;i++)
	{
		max=INF;
		for(j=1;j<=n;j++)
         if(!s[j]&&city[j]<max)
		 {
			 max=city[j];
			 rec=j;
		 }
		 s[rec]=1;
		 sum+=city[rec];
		 for(j=1;j<=n;j++)
			 if(!s[j]&&road[rec][j]<city[j])
				 city[j]=road[rec][j];
			 }
	printf("%d\n",sum);
	}
	return 1;
}