#include <cstdio>

#define ABS(n) ((n) < 0 ? (-(n)) : (n))
int distance( int x1, int y1, int x2, int y2 )
{
    return ABS(x2-x1) + ABS(y2-y1);
}

int main()
{
    int N,Ni;
    int H;
    
    scanf("%d", &N);// test cases
    for( Ni = 0; Ni < N; Ni++ )
    {
        scanf("%d", &H);
        int * X1 = new int[H];
        int * X2 = new int[H];
        int i,j, min;
        
        for(i = 0; i < H; i++)
        {
            int x1, x2;
            scanf("%d%d", &x1, &x2);
            X1[i] = x1;
            X2[i] = x2;
        }
        
        //loaded   
        
        min = distance( X1[0],0, X2[0],0 );
        for(i = 0; i < H; i++)
        {
            for(j = 0; j < H; j++)
            {
                int d = distance( X1[i], i, X2[j], j );
                //printf("%d %d | %d %d | distance = %d\n", X1[i],i, X2[j],j, d);
                if( d < min )
                    min = d;
            }
        }
        
        printf("K prechodu reky je treba %d pontonu.\n", min);
    }
    
    return 0;
}