Algo-Trian

Algorithm/Graph/BFS/P1443 马的遍历.cpp

@@ -0,0 +1,48 @@
+#include <iostream>
+#include <vector>
+#include <queue>
+#include <tuple>
+#include <climits>
+using namespace std;
+
+const int INF = INT_MAX >> 1;
+int dx[] = {1, 2, 2, 1, -1, -2, -2, -1};
+int dy[] = {2, 1, -1, -2, -2, -1, 1, 2};
+
+bool check(int bx, int by, int x, int y) {
+    return (x >= 0 && x < bx && y >= 0 && y < by);
+}
+
+int main() {
+    int n, m, x, y;
+    cin >> n >> m >> x >> y;
+    vector<vector<int>> mp(n, vector<int>(m, INF));
+
+    x--; y--; // ת<><D7AA><EFBFBD><EFBFBD> 0-based
+    queue<tuple<int, int, int>> q;
+    q.push({x, y, 0});
+    mp[x][y] = 0;
+
+    while (!q.empty()) {
+        auto [qx, qy, path] = q.front();
+        q.pop();
+
+        for (int i = 0; i < 8; i++) {
+            int nx = qx + dx[i];
+            int ny = qy + dy[i];
+            if (check(n, m, nx, ny) && mp[nx][ny] == INF) {
+                mp[nx][ny] = path + 1;
+                q.push({nx, ny, path + 1});
+            }
+        }
+    }
+
+    for (auto &row : mp) {
+        for (auto v : row) {
+            cout << (v == INF ? -1 : v) << " ";
+        }
+        cout << "\n";
+    }
+    return 0;
+}
+