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#include<bits/stdc++.h>
using namespace std;

// DCG 23

// You are given an M by N matrix consisting of booleans that represents a board. 
// Each True boolean represents a wall. Each False boolean represents a tile you can walk on.

// Given this matrix, a start coordinate, and an end coordinate, 
// return the minimum number of steps required to reach the end coordinate from the start. 
// If there is no possible path, then return null. You can move up, left, down, and right. 
// You cannot move through walls. You cannot wrap around the edges of the board.

// For example, given the following board:

// [[f, f, f, f],
// [t, t, f, t],
// [f, f, f, f],
// [f, f, f, f]]
// and start = (3, 0) (bottom left) and end = (0, 0) (top left), the minimum number of steps 
// required to reach the end is 7, since we would need to go through (1, 2) because there is a 
// wall everywhere else on the second row.

// input:
// 1
// 4 4
// 0 0 0 0 
// 1 1 0 1
// 0 0 0 0
// 0 0 0 0
// 3 0
// 0 0

// output:
// 7

vector< vector<int> > mat; // global

bool valid(int x, int y){
    if(x<0 || y<0 || x>=mat.size() || y>=mat[0].size() || mat[x][y] == 1){
        return false;
    }
    return true;
}

int minSteps(int sx,int sy, int dx, int dy){
    if(sx == dx && sy == dy){
        return 0; // base case
    }
    queue< pair<int,int> > Q;
    map< pair<int,int>, bool > visited;
    Q.push({sx,sy});
    visited[{sx,sy}]=true;
    int steps = 0;
    while( !Q.empty() ){
        int levelSize = Q.size();
        steps++;
        while(levelSize--){
            int currx = Q.front().first;
            int curry = Q.front().second;
            Q.pop();
            vector<int> comb = {-1,1};
            for(int i=0;i<2;i++){ // top, down
                    int newx=currx+comb[i];
                    if( valid(newx,curry) ){
                        if(newx == dx && curry == dy){
                            return steps;
                        }
                        if( !visited[{newx,curry}]){
                            Q.push({newx,curry});
                            visited[{newx,curry}]=true;
                        }
                    }
            }
            for(int i=0;i<2;i++){ // left, right
                    int newy=curry+comb[i];
                    if( valid(currx,newy) ){
                        if(currx == dx && newy == dy){
                            return steps;
                        }
                        if( !visited[{currx,newy}]){
                            Q.push({currx,newy});
                            visited[{currx,newy}]=true;
                        }
                    }
            }
        }
    }
    return -1;
}

int main(){
    freopen("ip.txt","r",stdin);
    int t;
    cin>>t;
    while(t--){
        int r,c;
        cin>>r>>c;
        mat.resize(r);
        for(int i=0;i<r;i++){
            mat[i].resize(c);
            for(int j=0;j<c;j++){
                // 1-block, 0-path
                cin>>mat[i][j];
            }
        }
        int sx,sy,dx,dy;
        cin>>sx>>sy;
        cin>>dx>>dy;
        cout<<minSteps(sx,sy,dx,dy)<<endl;;
        mat.resize(0);
    }
    return 0;
}