P7158 「dWoi R1」Password of Shady

R44423595

problem/P7158/P7158.cpp

@@ -0,0 +1,23 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+
+const int mod = 998244353;
+
+int t, n, k;
+long long f[100005], g[100005];
+
+int main() {
+    scanf("%d", &t);
+    f[1] = 8;
+    g[1] = 1;
+    for (int i = 2; i <= 100000; i++) {
+        f[i] = (f[i - 1] * 9 + g[i - 1]) % mod;
+        g[i] = (g[i - 1] * 9 + f[i - 1]) % mod;
+    }
+    while (t--) {
+        scanf("%d%d", &n, &k);
+        printf("%lld\n", n == 1 ? 9 : f[n]);
+    }
+    return 0;
+}