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| #include<bits/stdc++.h> using namespace std; #define int long long struct flowGraph { struct edge { int v, nxt, cap, flow; } edges[2222222]; int head[2222222], cnt = 0; int n, S, T; int maxflow = 0; int dist[2222222], cur[2222222]; void init(int _n, int _S, int _T) { memset(head, -1, sizeof(head)); cnt = 0; S = _S; T = _T; n = _n; } void addedge(int u, int v, int w) { edges[cnt] = {v, head[u], w, 0}; head[u] = cnt++; edges[cnt] = {u, head[v], 0, 0}; head[v] = cnt++; } bool bfs() { queue<int> q; memset(dist, 0, sizeof(int) * (n + 1)); dist[S] = 1; q.push(S); while (q.size()) { int u = q.front(); q.pop(); for (int i = head[u]; ~i; i = edges[i].nxt) { int v = edges[i].v; if ((!dist[v]) && (edges[i].cap > edges[i].flow)) { dist[v] = dist[u] + 1; q.push(v); } } } return dist[T]; } int dfs(int u, int flow) { if ((u == T) || (!flow)) { return flow; } int res = 0; for (int &i = cur[u]; ~i; i = edges[i].nxt) { int v = edges[i].v, f; if ((dist[v] == dist[u] + 1) && (f = dfs(v, min(flow - res, edges[i].cap - edges[i].flow)))) { res += f; edges[i].flow += f; edges[i ^ 1].flow -= f; if (res == flow) { return res; } } } return res; } int dinic() { while (bfs()) { memcpy(cur, head, sizeof(int) * (n + 1)); maxflow += dfs(S, 0x3f3f3f3f3f3f); } return maxflow; } } g; int dir[4][2] = {{1, 1}, {1, -1}, {-1, 1}, {-1, -1}}; int n, a, b; bool calc1(int x, int y) { int ta = a, tb = b; while (ta % 2 == 0 && tb % 2 == 0) { ta /= 2; tb /= 2; x /= 2; y /= 2; } if ((ta + tb) % 2) { return (x + y) % 2; } else { return x % 2; } } int calc2(int x, int y) { return x * n + y; } signed main() { cin >> n >> a >> b; vector<vector<char>> s(n + 1, vector<char>(n + 1)); for (int i = 1; i <= n; i++) { for (int j = 1; j <= n; j++) { cin >> s[i][j]; } } g.init(n * n + n + 2, 0, n * n + n + 1); for (int i = 1; i <= n; i++) { for (int j = 1; j <= n; j++) { if (s[i][j] == '#') { continue; } if (!calc1(i, j)) { g.addedge(0, calc2(i, j), 1); for (int k = 0; k < 4; k++) { int dx = i + dir[k][0] * a; int dy = j + dir[k][1] * b; if (1 <= dx && dx <= n && 1 <= dy && dy <= n && s[dx][dy] != '#') { g.addedge(calc2(i, j), calc2(dx, dy), 1); } dx = i + dir[k][0] * b; dy = j + dir[k][1] * a; if (1 <= dx && dx <= n && 1 <= dy && dy <= n && s[dx][dy] != '#') { g.addedge(calc2(i, j), calc2(dx, dy), 1); } } } else { g.addedge(calc2(i, j), n * n + n + 1, 1); } } } g.dinic(); vector<bool> vis(n * n + n + 1, 0); queue<int> q; q.push(0); vis[0] = 1; while (!q.empty()) { int u = q.front(); q.pop(); for (int i = g.head[u]; ~i; i = g.edges[i].nxt) { if (g.edges[i].cap > g.edges[i].flow && !vis[g.edges[i].v]) { vis[g.edges[i].v] = 1; q.push(g.edges[i].v); } } } vector<string> ans(n + 1, string(n + 1, '.')); for (int i = 1; i <= n; i++) { for (int j = 1; j <= n; j++) { if (s[i][j] == '#') { ans[i][j] = '#'; continue; } if (!calc1(i, j)) { if (vis[calc2(i, j)]) { ans[i][j] = 'o'; } else { ans[i][j] = '.'; } } else { if (!vis[calc2(i, j)]) { ans[i][j] = 'o'; } else { ans[i][j] = '.'; } } } } for (int i = 1; i <= n; i++) { for (int j = 1; j <= n; j++) { cout << ans[i][j]; } cout << '\n'; } return 0; }
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