#include<iostream>

 #include<vector>

 #include<string>

 #include<cmath>

 #include<set>

 #include<algorithm>

 #include<cstdio>

 #include<map>

 #include<cstring>

 using namespace std;

 int dis[][];

 struct Edge

 {

     int a, b;

     int cost;

 }edge[];

 int Tree[];

 int findRoot(int x)

 {

     if(Tree[x] == -)

         return x;

     int tmp = findRoot(Tree[x]);

     Tree[x] = tmp;

     return tmp;

 }

 bool cmp(Edge e1, Edge e2)

 {

     return e1.cost < e2.cost;

 }

 int main()

 {

     int n;

     scanf("%d", &n);

     for(int i = ; i <= n; ++i)

         Tree[i] = -;

     for(int i = ; i <= n; ++i)

         for(int j = ; j <= n; ++j)

             scanf("%d", &dis[i][j]);

     int q;

     scanf("%d", &q);

     for(int i = ; i <= q; ++i)

     {

         int a, b;

         scanf("%d %d", &a, &b);

         dis[a][b] = ;

     }

     int k = ;

     for(int i = ; i <= n; ++i)

         for(int j = ; j <= n; ++j)

         {

             if(i != j && i < j)    // 注意同一条边不要重复保存！

             {

                 edge[k].a = i;

                 edge[k].b = j;

                 edge[k].cost = dis[i][j];

                 ++k;

             }

         }

     sort(edge+, edge+k, cmp);

     int ans = ;

     for(int i = ; i < k; ++i)

     {

         int ra = findRoot(edge[i].a);

         int rb = findRoot(edge[i].b);

         if(ra != rb)

         {

             Tree[ra] = rb;

             ans += edge[i].cost;

         }

     }

     printf("%d\n", ans);

     return ;

 }