Zoj 3814 sawtooth puzzle)

Zoj 3814 sawtooth puzzle

Question Link

A wide range of searches are recorded, and 9 puzzles are compressed into one state and then searched, which means the simulation process is troublesome.

Code:

#include <cstdio>#include <cstring>#include <queue>#include <algorithm>#include <set>using namespace std;typedef unsigned long long ll;int t;int tmpg[10][10];ll rotate(ll x) {for (int i = 7; i >= 0; i--) {for (int j = 7; j >= 0; j--) {if (x % 2) tmpg[i][j] = 1;else tmpg[i][j] = 0;x /= 2;}}ll ans = 0;for (int i = 0; i < 8; i++) {for (int j = 0; j < 8; j++) {ans = ans * 2 + tmpg[7 - j][i];}}return ans;}struct Puzz {ll s[4];void init(char str[][10]) {s[0] = 0;for (int i = 0; i < 8; i++) {for (int j = 0; j < 8; j++) {s[0] = s[0] * 2;if (str[i][j] == '#')s[0]++;}}for (int i = 1; i < 4; i++)s[i] = rotate(s[i - 1]);}} sp[10], ep[10];char str[3][3][10][10];struct State {int u[10];int h;State() {memset(u, 0, sizeof(u)); h = 0;}void hash() {int ans = 0;for (int i = 0; i < 9; i++)ans = ans * 4 + u[i];h = ans;}};int chi[9][4];set<int> save;void dfs2(int u, int hash) {if (u == 9) {save.insert(hash);return;}for (int i = 0; i < 4; i++) {if (sp[u].s[i] == ep[u].s[0])dfs2(u + 1, hash * 4 + i);}}void build_set() {save.clear();dfs2(0, 0);}void init() {for (int i = 0; i < 3; i++) {for (int j = 0; j < 8; j++) {for (int k = 0; k < 3; k++) {scanf("%s", str[i][k][j]);}}}for (int i = 0; i < 3; i++) {for (int j = 0; j < 3; j++) {sp[i * 3 + j].init(str[i][j]);}}for (int i = 0; i < 3; i++) {for (int j = 0; j < 8; j++) {for (int k = 0; k < 3; k++) {scanf("%s", str[i][k][j]);}}}for (int i = 0; i < 3; i++) {for (int j = 0; j < 3; j++) {ep[i * 3 + j].init(str[i][j]);}}build_set();for (int i = 0; i < 9; i++) {for (int j = 0; j < 4; j++) {scanf("%d", &chi[i][j]);}}}const int INF = 0x3f3f3f3f;int vis[300005];const int d[4][2] = {{0, -1}, {-1, 0}, {0, 1}, {1, 0}};State v, v2;int vv[10];int to[4];bool dfs(int now, int rot) {vv[now] = 1;bool flag = false;for (int i = 0; i < 4; i++) {int x = now / 3 + d[i][0];int y = now % 3 + d[i][1];if (x < 0 || x >= 3 || y < 0 || y >= 3) continue;int next = x * 3 + y;if (vv[next]) continue;int uu = (i - v.u[now] + 4) % 4;if (chi[now][uu] == 0 || chi[next][(to[i] - v.u[next] + 4) % 4] == 0) continue;dfs(next, !rot);flag = true;}if (rot == 0) {v.u[now] = (v.u[now] + 1) % 4;v2.u[now] = (v2.u[now] + 3) % 4;}else {v.u[now] = (v.u[now] + 3) % 4;v2.u[now] = (v2.u[now] + 1) % 4;}return flag;}int bfs() {if (save.size() == 0) return -1;queue<State> Q;memset(vis, INF, sizeof(vis));State s;Q.push(s);vis[s.h] = 0;while (!Q.empty()) {State u = Q.front();if (save.find(u.h) != save.end())return vis[u.h];Q.pop();for (int j = 0; j < 9; j++) {memset(vv, 0, sizeof(vv));v = u;v2 = u;bool tmp = dfs(j, 0);v.hash(); v2.hash();if (vis[v.h] > vis[u.h] + 1) {vis[v.h] = vis[u.h] + 1;Q.push(v);}if (tmp && vis[v2.h] > vis[u.h] + 1) {vis[v2.h] = vis[u.h] + 1;Q.push(v2);}}}return -1;}int main() {to[3] = 1; to[1] = 3;to[2] = 0; to[0] = 2;scanf("%d", &t);while (t--) {init();printf("%d\n", bfs());}return 0;}

Zoj 3814 sawtooth puzzle)