#include <cstdlib>
#include <iostream>
#include <cstring>
#include <cstdio>
#include <vector>

using namespace std;

const int MAX_NODE = 100+2;
const int maxint = 0x7fffffff;

struct Edge
{
	int vertex;
	int cost;
};
vector<Edge> Graph[MAX_NODE];

struct Record
{
       int id;
       int key;
};

int pos[MAX_NODE];            //!!!! positon in heap for node i

      Record h[MAX_NODE];
      int size;
      void GoUp(int j)
      {
           int i;
           Record x = h[j];
           while ( j > 1)
           {
                 i = j/2;
                 if (x.key >= h[i].key) break;
                 h[j]= h[i];                     //i goes down
                 pos[h[i].id] = j;
                 j = i;
           }
           h[j] = x;
           pos[x.id] = j;
      }
      void GoDown(int i)
      {
           int j;
           Record x = h[i];
           while (2*i <= size)
           {
                 j = 2*i;
                 if (j < size && h[j].key > h[j+1].key) j++;
                 if (x.key <= h[j].key) break;
                 h[i] = h[j];
                 pos[h[j].id] = i;
           }
           h[i] = x;
           pos[x.id] = i;
      }
      Record Pop()
      {
             Record re = h[1];
             pos[re.id] = -1;        //already coming out
             h[1] = h[size];
             pos[h[size].id] = 1;
             size--;
             GoDown(1);
             return re;  
      }
      void InitHeap(int n)
      {
           int i;
           for (i=1; i<=n; i++)
           {
               h[i].id = i;
               if (i == 1) h[1].key = 0;
               else h[i].key = maxint;
               pos[i] = i;
           }
           size = n;
      }

int Prim(int n)
{
    int ans = 0;
    int i, j;
    Record min;
    InitHeap(n);
    for (i=1; i<=n; i++)
    {
         min = Pop();
         int v = min.id;
         int c = min.key;
         ans += c;
         for (j=1; j<=Graph[i].size(); j++)
         {
             int u = Graph[v][j-1].vertex;
             if (pos[u] != -1 && Graph[v][j-1].cost < h[pos[u]].key)
             {
                  h[pos[u]].key = Graph[v][j-1].cost;
                  GoUp(pos[u]);
             }
         }
    }
    return ans;  
}

int main(int argc, char *argv[])
{
    int N, Q;
    int i, j;
    int c, u, v;
	//freopen("test.txt", "r", stdin);
    scanf("%d", &N);
	Edge e;
    for (i=1; i<=N; i++)
    {
        for (j=1; j<=N; j++)
        {
            scanf("%d", &c);
			if (i == j) continue;
			e.vertex = j;
			e.cost = c;
			Graph[i].push_back(e);
			e.vertex = i;
			Graph[j].push_back(e);
        }
    }
    scanf("%d", &Q);
    for (i=1; i<=Q; i++)
    {
         scanf("%d %d", &u, &v);
		 for (j=1; j<=Graph[u].size(); j++)
		 {
			 if (Graph[u][j-1].vertex == v)
				 Graph[u][j-1].cost = 0;
		 }
		 for (j=1; j<=Graph[v].size(); j++)
		 {
			 if (Graph[v][j-1].vertex == u)
				 Graph[v][j-1].cost = 0;
		 } 
    }
    int ans = 0; 
	ans = Prim(N);
    printf("%d\n", ans);
   // system("PAUSE");
    return EXIT_SUCCESS;
}