why i got crash (access vio..) in this code for problem 1008,pls help me

#include <stdio.h>
struct node
 {
   long x,y;
 };
struct node que[155];
long sf=-1,sl=-1;
long graph[11][11],know[11][11];
void bfs(long i,long j)
{
  if(i>=0&&i<=9&&(j+1)>=0&&(j+1)<=9&&graph[i][j+1]&&!know[i]
[j+1])
    { sl++; que[sl].x=i; que[sl].y=j+1; know[i][j+1]=1; printf("R"); }
  if((i-1)>=0&&(i-1)<=9&&j>=0&&j<=9&&graph[i-1][j]&&!know[i-1][j])
    { sl++; que[sl].x=i-1; que[sl].y=j; know[i-1][j]=1; printf("B"); }
  if(i>=0&&i<=9&&(j-1)>=0&&(j-1)<=9&&graph[i][j-1]&&!know[i][j-1])
    { sl++; que[sl].x=i; que[sl].y=j-1; know[i][j-1]=1; printf("L"); }
  if((i+1)>=0&&(i+1)<=9&&j>=0&&j<=9&&graph[i+1][j]&&!know[i+1]
[j])
    { sl++; que[sl].x=i+1; que[sl].y=j; know[i+1][j]=1; printf("T"); }
  while(sf<sl)
    {
       printf(",\n");
       sf++;
       bfs(que[sf].x,que[sf].y);
    }
}

int main()
{
 long n,tmp1,tmp2;
 long bi,bj,i;
 scanf("%ld",&n);
 scanf("%ld %ld",&bj,&bi);
  graph[bi-1][bj-1]=1;
  for(i=1;i<n;i++)
   {
    scanf("%ld %ld",&tmp2,&tmp1);
     graph[tmp1-1][tmp2-1]=1;
   }
 printf("%ld %ld\n",bj,bi);
 bi--; bj--;
 know[bi][bj]=1;
 bfs(bi,bj);
 printf(".");
 return 0;
}