Laughhing bomb samsung

/* laughing bomb
INDEXING IS 1 BASED SO ARE THE INPUTS

INPUTS
2
7 8
0 0 1 1 0 0 0
1 1 1 1 0 1 0
0 0 1 1 1 1 1
0 1 1 1 1 1 1
0 1 0 0 1 1 0
0 1 1 1 1 0 0
0 0 1 0 1 1 1
0 0 0 0 1 0 0
2 5
10 10
1 1 1 1 0 1 1 0 0 0
0 1 1 1 1 1 0 1 1 0
0 0 1 1 0 1 0 1 1 1
0 1 1 1 1 1 0 0 1 1
0 1 0 1 0 1 1 1 1 0
0 0 0 0 0 1 1 0 0 0
1 0 1 0 1 0 1 1 0 0
0 0 1 1 1 1 1 1 1 1
1 0 1 0 0 1 0 1 1 0
1 1 1 0 0 0 0 1 1 1
2 2

OUTPUTS
8
21

*/
#include<iostream>
using namespace std;

struct node{
  int x;
  int y;
  int l;
};

int sx,sy;
node q[100000];
bool vis[1000][1000];
int front,back;
int n,m;
int a[100][100];
int ans;

void init(){
    front = back = 0;
}
void push(int x, int y, int l){
    q[back].x = x;
    q[back].y = y;
    q[back].l = l;
    back++;
}
node pop(){
    return q[front++];
}
bool empty(){
    return front == back;
}

bool valid(int x, int y){
    return (x>=0 && x<n && y>=0 && y<m && !vis[x][y]);
}

int dx[] = {-1,0,1,0};
int dy[] = {0,1,0,-1};


void solve(){

    if(a[sx][sy] == 0)return;

    vis[sx][sy] = true;
    push(sx,sy,1);


    while(!empty()){

        node temp = pop();

        int x,y,l;
        x = temp.x;
        y = temp.y;
        l = temp.l;


        ans = max(ans,l);


        for(int i = 0; i<4; i++){

            int xx = x + dx[i];
            int yy = y + dy[i];

            if(valid(xx,yy) && a[xx][yy] == 1){
                vis[xx][yy] = true;
                push(xx,yy,l+1);
            }

        }

    }

}

int main(){

    int t; cin>>t;
    while(t--){

        /* FIRST COLUMN IS TAKEN AS INPUT AND THEN ROW ACC. TO TEST CASES */
        cin>>m>>n;


        for(int i =0; i<n;i++){
            for(int j = 0; j<m; j++){
                vis[i][j] = false;
                cin>>a[i][j];
            }
        }
        /* acc to the test cases first col is taken as input and then row
           I have taken the input as row and then col so write it down as
           cin>>sy>>sx
        */
        cin>>sx>>sy;
        sx--; sy--;  /* zero based indexing */
        init();
        ans = -1;
        solve();
        cout<<ans<<endl;
    }


    return 0;
}