#include #include #include #include #include #include #include #define ll long long #define PLL pair #define VS vector #define VL vector #define rep(i,a) for (ll i=0;i (const NODE &node1, const NODE &node2) { return node1.dist > node2.dist; } NODE nodes[202][202]; bool flag[202][202]; void update(priority_queue ,greater > &pq,NODE node,ll x, ll y) { //cout << "update:" << x << " " << y << flag[x][y]< node.dist + nodes[x][y].level) { nodes[x][y].dist = nodes[x][y].level + node.dist; if (!flag[x][y]) { //cout << "yala" << endl; flag[x][y] = true; pq.push(nodes[x][y]); //cout << "update_pq_size=" << pq.size() << endl; } } } int main() { ll N, V, Ox, Oy; cin >> N >> V >> Ox >> Oy; rep(i, N) rep(j, N) { cin >> nodes[i][j].level; nodes[i][j].dist = -1; nodes[i][j].x = i; nodes[i][j].y = j; flag[i][j] = false; } ll cost; priority_queue, greater > pq; nodes[0][0].dist = 0; pq.push(nodes[0][0]); NODE node; while (!pq.empty()) { node = pq.top(); pq.pop(); //cout << node.x << " " << node.y << endl; flag[node.x][node.y] = false; if (node.x > 0) { update(pq, node, node.x - 1, node.y); } if (node.x < N - 1) { update(pq, node, node.x + 1, node.y); } if (node.y > 0) { update(pq, node, node.x, node.y - 1); } if (node.y < N - 1) { update(pq, node, node.x, node.y + 1); } //cout << "main_pq_size=" << pq.size() << endl; }ll start_to_end = V - nodes[N - 1][N - 1].dist; if (start_to_end > 0){ cout << "YES" << endl; exit(0); } if (start_to_end <= 0 && Ox == 0 && Oy == 0){ cout << "NO" << endl; exit(0); } ll start_to_O = (V - nodes[Ox - 1][Oy - 1].dist)*2; if (start_to_O <= 0){ cout << "NO" << endl; exit(0); } rep(i, N) rep(j, N) nodes[i][j].dist = -1; nodes[Ox - 1][Oy - 1].dist = 0; pq.push(nodes[Ox - 1][Oy - 1]); while (!pq.empty()) { node = pq.top(); pq.pop(); //cout << node.x << " " << node.y << endl; flag[node.x][node.y] = false; if (node.x > 0) { update(pq, node, node.x - 1, node.y); } if (node.x < N - 1) { update(pq, node, node.x + 1, node.y); } if (node.y > 0) { update(pq, node, node.x, node.y - 1); } if (node.y < N - 1) { update(pq, node, node.x, node.y + 1); } //cout << "main_pq_size=" << pq.size() << endl; }ll O_to_end = start_to_O - nodes[N - 1][N - 1].dist; cout << (O_to_end > 0 ? "YES" : "NO") << endl; return 0; }