#include<stdio.h>
#define max 101
typedef struct Graph{
	long ArrayGraph[max][max];
    int Vnum;
}Graph;

 typedef struct CTree{
	int  TVex[max],Tnum;
	int  LVex[max],Lnum;
}CTree;

typedef struct MinVex{
	int  i;
	long  Weight;
}MinVex;
Graph CurGraph;
CTree CurTree;

void InsertCTree(int Vnum);
int  FindMin(long *MinWeight);

int main()
{
	
    int  i,j,Xnum,aa[max][max];
	long MinWeight=0;
    scanf("%d",&CurGraph.Vnum);
    
	 for(i=0;i<CurGraph.Vnum;i++)
	    for(j=0;j<CurGraph.Vnum;j++)
		  scanf("%ld",&CurGraph.ArrayGraph[i][j]);
	  scanf("%d",&Xnum);
	  for(i=0;i<Xnum;i++)
		  { scanf("%d%d",&aa[i][0],&aa[i][1]);
		    CurGraph.ArrayGraph[aa[i][0]-1][aa[i][1]-1]=0;
	     /*	CurGraph.ArrayGraph[aa[i][1]-1][aa[i][0]-1]=0;*/
		  }
       CurTree.Lnum=0;
	   CurTree.Tnum=0;
	   for(i=0;i<CurGraph.Vnum;i++){
          CurTree.LVex[i]=i;
		  CurTree.Lnum++;
	   }
	   InsertCTree(0);
       while(CurTree.Lnum!=0){
		  i=FindMin(&MinWeight);
		  InsertCTree(i);
	   }	   
	   printf("%ld\n",MinWeight);	   
       
	

       return 1;

}

void InsertCTree(int Vnum)
{
   int i,j;

  
   for(i=0;i<CurTree.Lnum;i++)
	   if(CurTree.LVex[i]==Vnum)
		   break;
	   
   if(i>=CurTree.Lnum)
	   return;
   
   for(j=i;j<CurTree.Lnum;j++)
	   CurTree.LVex[j]=CurTree.LVex[j+1];
   
   CurTree.Lnum--;

   CurTree.TVex[CurTree.Tnum]=Vnum;
   CurTree.Tnum++;

   return;
}


int FindMin(long *MinWeight)
{
   MinVex CurMinVex;
   int i,j;

   CurMinVex.Weight=10001;
   
   for(i=0;i<CurTree.Tnum;i++)
	   for(j=0;j<CurTree.Lnum;j++)
		   if(CurGraph.ArrayGraph[CurTree.TVex[i]][CurTree.LVex[j]]<CurMinVex.Weight){
				CurMinVex.i=CurTree.LVex[j];
				CurMinVex.Weight=CurGraph.ArrayGraph[CurTree.TVex[i]][CurTree.LVex[j]];
		   }

   *MinWeight+=CurMinVex.Weight;

  return CurMinVex.i;
}