#include<cstdio>
#include<cstring>
#include<iostream>
#define num(i,j) (i-1)*m+j
#define N 505
using namespace std;
const int dx[10]={0,1,1,-1,-1,1,-1},dy[10]={0,1,-1,1,-1,0,0,1,-1};
int a[N][N],b[N][N],fa[N*N],T,n,m,x,y,q,ans;
char s[N];
struct he{
    int l,r;
}data[N*N];
int gf(int x){
    if(x==fa[x]) return x;return fa[x]=gf(fa[x]);
}
void init(){
    memset(fa,0,sizeof(fa));
    memset(a,0,sizeof(a));
    memset(b,0,sizeof(b));
    memset(data,0,sizeof(data));
}
int main(){
    scanf("%d",&T);
    while(T--){
        init();
        scanf("%d%d",&n,&m);
        for(int i=1;i<=n;i++) {
            scanf("%s",s);
            for(int j=1;j<=m;j++){
                if(s[j-1]=='1') a[i][j]=1;
                fa[num(i,j)]=num(i,j);
                data[num(i,j)].l=data[num(i,j)].r=j;
            }
        }
        ans=-1;
        for(int i=1;i<=n;i++) 
            for(int j=1;j<=m;j++)
            if(a[i][j]){
                b[i][j]=1;
                for(int o=1;o<=8;o++){
                    int x1=i+dx[o];
                    int y1=j+dy[o];
                    if(x1<1||y1<1||x1>n||y1>m||!a[x1][y1]||!b[i][j]) continue;
                    int u=gf(num(i,j)),v=gf(num(x1,y1));
                    if(u!=v){
                        fa[u]=v;
                        data[v].l=min(data[u].l,data[v].l);
                        data[v].r=max(data[v].r,data[u].r);
                        if(data[v].l==1&&data[v].r==m) ans=0;
                    }
                }
            }
        scanf("%d",&q);
        for(int i=1;i<=q;i++){
            scanf("%d%d",&x,&y);
            x++;y++;
            a[x][y]=1;
            for(int o=1;o<=8;o++){
                int x1=x+dx[o];
                int y1=y+dy[o];
                if(x1<1||y1<1||x1>n||y1>m||!a[x1][y1]) continue;
                int u=gf(num(x,y)),v=gf(num(x1,y1));
                if(u!=v){
                    fa[u]=v;
                    data[v].l=min(data[u].l,data[v].l);
                    data[v].r=max(data[v].r,data[u].r);
                    if(data[v].l==1&&data[v].r==m&&ans==-1) ans=i;
                }
            }
        }
        printf("%d\n",ans);
    }
}