import heapq

def main():
    import sys
    input = sys.stdin.read().split()
    idx = 0
    H = int(input[idx]); idx +=1
    W = int(input[idx]); idx +=1
    Y = int(input[idx]); idx +=1
    X = int(input[idx]); idx +=1
    Y -=1
    X -=1
    
    A = []
    for _ in range(H):
        row = list(map(int, input[idx:idx+W]))
        idx += W
        A.append(row)
    
    sum_attack = A[Y][X]
    visited = [[False for _ in range(W)] for _ in range(H)]
    visited[Y][X] = True
    
    heap = []
    directions = [(-1,0), (1,0), (0,-1), (0,1)]
    for dy, dx in directions:
        ny = Y + dy
        nx = X + dx
        if 0 <= ny < H and 0 <= nx < W:
            val = A[ny][nx]
            if val <= sum_attack and not visited[ny][nx]:
                heapq.heappush(heap, (val, ny, nx))
                visited[ny][nx] = True
    
    while heap:
        val, i, j = heapq.heappop(heap)
        sum_attack += val
        for dy, dx in directions:
            ni = i + dy
            nj = j + dx
            if 0 <= ni < H and 0 <= nj < W:
                if not visited[ni][nj] and A[ni][nj] <= sum_attack:
                    heapq.heappush(heap, (A[ni][nj], ni, nj))
                    visited[ni][nj] = True
    
    for i in range(H):
        for j in range(W):
            if (i, j) == (Y, X):
                continue
            if not visited[i][j]:
                print("No")
                return
    print("Yes")

if __name__ == "__main__":
    main()