P1443 马的遍历

R43073005

problem/P1443/P1443.cpp

@@ -0,0 +1,39 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+
+int n, m, x, y, vis[405][405];
+
+const int dx[] = {0, -2, -2, -1, -1, +1, +1, +2, +2};
+const int dy[] = {0, -1, +1, -2, +2, -2, +2, -1, +1};
+
+inline void bfs(int x, int y) {
+    queue<pair<int, int>> q;
+    q.push(make_pair(x, y));
+    while (!q.empty()) {
+        int xx = q.front().first;
+        int yy = q.front().second;
+        q.pop();
+        for (int i = 1; i <= 8; i++) {
+            int u = xx + dx[i];
+            int v = yy + dy[i];
+            if (u < 1 || u > n || v < 1 || v > m || vis[u][v] != -1) continue;
+            q.push(make_pair(u, v));
+            vis[u][v] = vis[xx][yy] + 1;
+        }
+    }
+}
+
+int main() {
+    memset(vis, 0xff, sizeof(vis));
+    scanf("%d%d%d%d", &n, &m, &x, &y);
+    vis[x][y] = 0;
+    bfs(x, y);
+    for (int i = 1; i <= n; i++) {
+        for (int j = 1; j <= m; j++) {
+            printf("%-5d", vis[i][j]);
+        }
+        printf("\n");
+    }
+    return 0;
+}