#include #include #include #include #include #include #include #include using namespace std; #define GET_ARG(a,b,c,F,...) F #define REP3(i,s,e) for (i = s; i <= e; i++) #define REP2(i,n) REP3 (i,0,(int)(n)-1) #define REP(...) GET_ARG (__VA_ARGS__,REP3,REP2) (__VA_ARGS__) #define RREP3(i,s,e) for (i = s; i >= e; i--) #define RREP2(i,n) RREP3 (i,(int)(n)-1,0) #define RREP(...) GET_ARG (__VA_ARGS__,RREP3,RREP2) (__VA_ARGS__) #define DEBUG(x) cerr << #x ": " << x << endl string f[50]; int dx[] = {1,0,-1,0}; int dy[] = {0,1,0,-1}; bool used[50][50]; int h, w; void dfs(int y, int x) { int i; used[y][x] = true; REP (i,4) { int ny = y + dy[i]; int nx = x + dx[i]; if (ny < 0 || ny >= h || nx < 0 || nx >= w) continue; if (!used[ny][nx] && abs(f[y][x]-f[ny][nx]) <= 1) { dfs(ny,nx); } ny += dy[i]; nx += dx[i]; if (ny < 0 || ny >= h || nx < 0 || nx >= w) continue; if (!used[ny][nx] && f[y][x] == f[ny][nx]) { dfs(ny,nx); } } } int main(void) { int i, sx, sy, gx, gy; cin >> h >> w; cin >> sy >> sx >> gy >> gx; sx--; sy--; gx--; gy--; REP (i,h) cin >> f[i]; dfs(sy,sx); if (used[gy][gx]) puts("YES"); else puts("NO"); return 0; }