#include<bits/stdc++.h>
char map[50][51];
int flag[50][50];
int H,W,Sx,Sy,Gx,Gy;
void dfs(int y,int x){
    if(flag[y][x])return;
    flag[y][x] = 1;
    int dx[] = {1,0,-1,0,2,0,-2,0}, dy[] = {0,1,0,-1,0,2,0,-2};
    for(int i = 0;i < 8;i++){
        int nx = x+dx[i],ny = y+dy[i];
        if(0<=nx && nx<W && 0<=ny && ny<H){
            int dh = abs((map[ny][nx]-'0')-(map[y][x]-'0'));
            if(i < 4 && dh <= 1)dfs(ny,nx);
            else if(dh == 0 && map[y+dy[i-4]][x+dx[i-4]] < map[y][x])dfs(ny,nx);
        }
    }
}
main(){
    scanf("%d%d%d%d%d%d",&H,&W,&Sx,&Sy,&Gx,&Gy);
    for(int i = 0;i < H;i++)scanf("%s",map[i]);
    dfs(Sx-1,Sy-1);
    printf("%s\n",flag[Gx-1][Gy-1]?"YES":"NO");
}