feat: new solution code.

ra-preguicosa/src/ac.cpp

@@ -1,8 +1,128 @@
 #include <bits/stdc++.h>
 
+#define endl '\n'
+#define INF 0x3f
+
 using namespace std;
 
+typedef pair<int, int> pii;
 
-int main(){
+const int MAXN = 1e3 + 10;
+
+int C, L, W;
+int Cr, Lr, Cs, Ls;
+int alagado[MAXN][MAXN];
+const int COSTS[5][5] = {
+    {7, 6, 5, 6, 7},
+    {6, 3, 2, 3, 6},
+    {5, 2, 0, 2, 5},
+    {6, 3, 2, 3, 6},
+    {7, 6, 5, 6, 7},
+};
+int vis[MAXN][MAXN];
+int g[MAXN][MAXN];
+
+bool valid(int c, int l) {
+   return c > 0 && c <= C && l > 0 && l <= L && alagado[c][l] == 0; 
+}
+
+int h(int c, int l)
+{
+   return sqrt(abs(Cs - c)*abs(Cs - c) + abs(Ls - l)*abs(Ls - l));
+}
+
+bool reachable()
+{
+   queue<pii> q;
+   memset(vis, 0, sizeof(vis));
+
+   q.push({Cr, Lr});
+   vis[Cr][Lr] = 1;
+
+   while (!q.empty())
+   {
+      auto [c, l] = q.front();
+      q.pop();
+
+      if (c == Cs && l == Ls) return true;
+
+      for (int i = -2; i <= 2; i++){
+         for (int j = -2; j <= 2; j++){
+            int nc = c + i, nl = l + j;
+            if (!valid(nc, nl) || vis[nc][nl]) continue;
+            vis[nc][nl] = 1;
+            q.push({nc, nl});
+         }
+      }
+   }
+
+   return false;
+}
+
+void solve()
+{
+   if (!reachable())
+   {
+      cout << "impossible" << endl;
+      return;
+   }
+
+   memset(vis, 0, sizeof(vis));
+   memset(g, INF, sizeof(g));
+   priority_queue<pair<int, pii>> pq;
+   g[Cr][Lr] = 0;
+   pq.push({-h(Cr, Lr), {Cr, Lr}});
+   while (!pq.empty()){
+      auto [curCost, curCoords] = pq.top();
+      pq.pop();
+
+      auto [c, l] = curCoords;
+
+      if (vis[c][l]) continue;
+      vis[c][l] = 1;
+
+      if (c == Cs && l == Ls){
+         cout << g[c][l] << endl;
+         return;
+      }
+
+      for (int i = -2; i <= 2; i++){
+         for (int j = -2; j <= 2; j++){
+            int nc = c + i, nl = l + j;
+            if (!valid(nc, nl)) continue;
+
+            int cost = COSTS[i + 2][j + 2];
+            int newG = g[c][l] + cost;
+            if (newG < g[nc][nl]){
+               g[nc][nl] = newG;
+               int f = g[nc][nl] + h(nc, nl);
+               // insere custo negativo pois por padrao a priority queue é uma max heap
+               pq.push({-f, {nc, nl}});
+            }
+         }
+      }
+   }
+}
+
+int main()
+{
+   ios::sync_with_stdio(false);
+   cin.tie(nullptr);
+
+   while (cin >> C >> L, C && L){
+      cin >> Cr >> Lr;
+      cin >> Cs >> Ls;
+      cin >> W;
+      memset(alagado, 0, sizeof(alagado));
+      memset(vis, 0, sizeof(vis));
+      for (int i = 0; i < W; i++){
+         int C1, C2, L1, L2;
+         cin >> C1 >> L1 >> C2 >> L2;
+         for (int k = C1; k <= C2; k++)
+            for (int l = L1; l <= L2; l++)
+               alagado[k][l] = 1;
+      }
+      solve();
+   }
    return 0;
 }