#include <bits/stdc++.h>
#define rep(i,n) for(int i = 0; i < (n); i++)
using namespace std;
typedef long long ll;

int main(){
    cin.tie(0);
    ios::sync_with_stdio(0);
    
    int H,W,Y,X; cin >> H >> W >> Y >> X; Y--; X--;
    vector<vector<ll>> A(H, vector<ll>(W));
    ll sum = 0;
    rep(i,H)rep(j,W) {
        cin >> A[i][j];
        sum += A[i][j];
    }

    using T = tuple<ll,int,int>;
    priority_queue<T,vector<T>,greater<T>> q;
    ll cur = 0;
    vector<vector<bool>> used(H, vector<bool>(W, false));
    q.push({A[Y][X], Y, X});
    int di[] = {0, 1, 0, -1};
    int dj[] = {1, 0, -1, 0};
    used[Y][X] = true;
    while(!q.empty()) {
        auto [a, i, j] = q.top(); q.pop();
        if(!(i == Y && j == X) && cur <= a) {
            cout << "No" << endl;
            return 0;
        }
        cur += a;
        rep(d,4) {
            int ni = i + di[d], nj = j + dj[d];
            if(0 <= ni && ni < H && 0 <= nj && nj < W) {
                if(used[ni][nj] == false) {
                    q.push({A[ni][nj], ni, nj});
                    used[ni][nj] = true;
                }
            }
        }
    }

    cout << (sum == cur ? "Yes" : "No") << endl;
}