#include<cstdio>
#include<cstring>
#include<algorithm>
#include<cmath>
#include<iostream>
using namespace std;
const int N = 505;
const int M = 250050;
bool map[N][N];
int biao[N][N];
int fa[M];
int cc;
int n,m,p;
int s,t;
int ans;
int getint()
{
    int res=0;
    char ch=getchar();
    while((ch<'0' || ch>'9') && ch!='-')
        ch=getchar();
    bool fan=0;
    if(ch=='-')
    {
        fan=1;
        ch=getchar();
    }
    while('0'<=ch && ch<='9')
    {
        res=res*10+ch-'0';
        ch=getchar();
    }
    if(fan)
        res=-res;
    return res;
}
int getnum()
{
    int res=0;
    char ch=getchar();
    while((ch<'0' || ch>'9') && ch!='-')
        ch=getchar();
    return (ch-'0');
}
int Getf(int x)
{
    if(fa[x]!=x)
        fa[x]=Getf(fa[x]);
    return fa[x];
}
void Link(int x,int y)
{
    x=Getf(x);
    y=Getf(y);
    fa[x]=y;
}
void Add(int x,int y,int z)
{
    int i,j;
    for(i=x-1;i<=x+1;i++)
    {
        for(j=y-1;j<=y+1;j++)
        {
            if(i<1 || i>n)
                continue;
            if(j==0)
                Link(s,biao[x][y]);
            if(j==m+1)
                Link(t,biao[x][y]);
            if(map[i][j])
                Link(biao[i][j],biao[x][y]);
        }
    }
    if(Getf(s)==Getf(t))
        ans=min(ans,z);
}
int f()
{
    int i,j;
    n=getint();
    m=getint();
    for(i=1;i<=n;i++)
    {
        for(j=1;j<=m;j++)
            map[i][j]=getnum();
    }
    p=getint();
    ans=p+1;
    cc=0;
    for(i=1;i<=n;i++)
    {
        for(j=1;j<=m;j++)
        {
            cc++;
            biao[i][j]=cc;
            fa[cc]=cc;
        }
    }
    cc++;
    s=cc;
    fa[s]=s;
    cc++;
    t=cc;
    fa[t]=t;
    for(i=1;i<=n;i++)
    {
        for(j=1;j<=m;j++)
        {
            if(map[i][j])
                Add(i,j,0);
        }
    }
    for(i=1;i<=p;i++)
    {
        int a=getint()+1;
        int b=getint()+1;
        if(!map[a][b])
        {
            map[a][b]=1;
            Add(a,b,i);
        }
    }
    if(ans==p+1)
        ans=-1;
    return ans;
}
int main()
{
    int t=getint();
    while(t--)
        printf("%d\n",f());
    return 0;
}