B - Number Box

https://atcoder.jp/contests/abc258/submissions/32896593

AtCoder/ABC258/B/B.cpp

@@ -0,0 +1,57 @@
+#include <cstdio>
+#include <vector>
+
+const int N = 15;
+
+int n, a[N][N];
+long long ans;
+
+const int dx[] = {0, 1, 0, -1, 0, 1, 1, -1, -1},
+          dy[] = {0, 0, -1, 0, 1, 1, -1, 1, -1};
+
+std::vector<int> res;
+
+void dfs(int x, int y, int k, int cnt, long long sum, std::vector<int> s) {
+    if (x > n) x = 1;
+    if (x < 1) x = n;
+    if (y > n) y = 1;
+    if (y < 1) y = n;
+
+    if (cnt == n) {
+        if (sum > ans) {
+            ans = sum;
+            res = s;
+        }
+
+        return;
+    }
+
+    s.push_back(a[x][y]);
+
+    dfs(x + dx[k], y + dy[k], k, cnt + 1, sum * 10 + a[x][y], s);
+}
+
+int main() {
+    scanf("%d", &n);
+
+    for (int i = 1; i <= n; i++) {
+        for (int j = 1; j <= n; j++) {
+            scanf("%1d", &a[i][j]);
+        }
+    }
+
+    for (int i = 1; i <= n; i++) {
+        for (int j = 1; j <= n; j++) {
+            for (int k = 1; k <= 8; k++) {
+                dfs(i, j, k, 0, 0, std::vector<int>());
+            }
+        }
+    }
+
+    for (const int &x : res) {
+        printf("%d", x);
+    }
+    printf("\n");
+
+    return 0;
+}