/*kruskal算法Memory: 812K  Time: 329MSLanguage: C++  Result: Accepted*/#include<cstdio>#include<cstring>#include<cstdlib>const int MAXN = 505;int u[MAXN * MAXN], v[MAXN * MAXN], w[MAXN * MAXN], p[MAXN], r[MAXN * MAXN];int e1, res, n, m;

int find_set( int x){return p[x] == x ? x : ( p[x] = find_set( p[x]));}

int cmp( const void *_p, const void *_q){int *p = (int *)_p;int *q = (int *)_q;return w[*p] - w[*q];}

void kruskal(){//res = 0;    for( int i = 0; i < n; i ++) p[i] = i;for( int i = 0; i < m; i ++) r[i] = i;    qsort( r, m, sizeof(r[0]), cmp);for( int i = 0; i < m; i ++)    {int e = r[i]; int x = find_set(u[e]), y = find_set(v[e]);if( x != y) { res += w[e]; p[x] = y; e1 = e;}    }}

int main(){int T;    scanf( "%d", &T);while( T --)    {        scanf( "%d", &n);        m = 0;for( int i = 0; i < n; i ++)for( int j = 0; j < n; j ++)            {                u[m] = i, v[m] = j;                scanf( "%d", &w[m ++]);            }        kruskal();        printf( "%d\n", w[e1]);    }return 0;}

/*prim算法Memory: 564K  Time: 141MSLanguage: C++  Result: Accepted*/#include<cstdio>#include<cstring>#include<cstdlib>const int MAXN = 505;bool vis[MAXN];int w[MAXN][MAXN], lowc[MAXN], max, n, res;const int INF = 0x3F3F3F3F;void prim(){    max = 0;//res = 0;    int minc, p;    memset( vis, false, sizeof vis);    vis[0] = true;for( int i = 1; i < n; i ++) lowc[i] = w[0][i];for( int i = 1; i < n; i ++) {        minc = INF, p = -1;for( int j = 0; j < n; j ++)if( !vis[j] && minc > lowc[j]){                minc = lowc[j];                p = j;            }        vis[p] = true;        max = max > minc ? max : minc;//res += minc;// 更新lowc[j]的值。        for( int j = 0; j < n; j ++)if( !vis[j] && lowc[j] > w[p][j])                lowc[j] = w[p][j];    }}

int main(){int T;    scanf( "%d", &T);while( T --)    {        scanf( "%d", &n);for( int i = 0; i < n; i ++)for( int j = 0; j < n; j ++)                scanf( "%d", &w[i][j]);        prim();        printf( "%d\n", max);    }return 0;}

/*Accepted    800K    282MS    C++    1373B    2012-07-24 08:40:52*/
#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<algorithm>
using namespace std;const int MAXN = 505;
int p[MAXN], r[MAXN * MAXN], u[MAXN * MAXN], v[MAXN * MAXN], w[MAXN * MAXN];
int n, m, ret;bool cmp( const int i, const int j)
{return w[i] < w[j];
}int find(int x)
{return p[x] == x ? x : (p[x] = find(p[x]));
}void init()
{int i, j, val;m = 0;for( i = 1; i <= n; i ++)for( j = 1; j <= n; j ++){scanf( "%d", &val);if(i == j) continue;u[m] = i, v[m] = j, w[m ++] = val;}
}void kruskal()
{int ans, cnt, e;ans = cnt = 0;int nx, ny, i, j;for( i = 1; i <= n; i ++)p[i] = i;for( i = 0; i < m; i ++)r[i] = i;sort( r, r + m, cmp);for( i = 0; i < m; i ++){e = r[i];nx = find(u[e]), ny = find(v[e]);if( nx != ny){p[nx] = ny;ans += w[e];cnt ++;if( n - 1 == cnt) {ret = w[e];break;}}}
}int main()
{int T;scanf( "%d", &T);while( T --){scanf( "%d", &n);init();kruskal();printf( "%d\n", ret);//printf( "\n");
    }return 0;
}