#include<bits/stdc++.h>
using namespace std;
struct node
{
	int x,y;
};
queue<node> q;
int i,j,sx,sy,fx,fy,t,step[1001][1001],vis[1001][1001],n,m;
int dx[5]={0,-1,1,0,0};
int dy[5]={0,0,0,1,-1};
void bfs()
{
	node s;
	s.x=sx,s.y=sy;
	q.push(s);
	vis[sx][sy]=1;
	step[sx][sy]=1;
	if(sx==fx&&sy==fy)
	{
		cout<<"1";
		return;	
	}
	while(!q.empty())
	{
		node a=q.front();
		for(int i=1;i<=4;i++)
		{
			node now;
			now.x=a.x+dx[i];
			now.y=a.y+dy[i];
			if(now.x<1||now.x>n||now.y<1||now.y>n||vis[now.x][now.y]==1)
				continue;
			step[now.x][now.y]=step[a.x][a.y]+1;
			if(now.x==fx&&now.y==fy)
			{
				cout<<step[now.x][now.y];
				return;			
			}
			q.push(now);
		}
		q.pop();
	}
	cout<<"-1";
}
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    memset(vis,0,sizeof(vis));
	cin>>n>>m>>t>>sx>>sy>>fx>>fy;
	while(t--)
	{
		cin>>i>>j;
		vis[i][j]=1;
	}
	bfs();
    return 0;
}

有三个点MLE