P3599 Koishi Loves Construction

https://www.luogu.com.cn/record/92697061

Luogu/P3599/P3599.cpp

@@ -0,0 +1,76 @@
+#include <iostream>
+
+using std::cin;
+using std::cout;
+const char endl = '\n';
+
+const int N = 1e5 + 5;
+
+int x, t, n, a[N];
+
+bool is_prime(int x) {
+    if (x < 2) return false;
+
+    for (int i = 2; i * i <= x; i++) {
+        if (x % i == 0) return false;
+    }
+
+    return true;
+}
+
+int binpow(int a, int b, int p) {
+    int res = 1;
+
+    while (b) {
+        if (b & 1) res = 1ll * res * a % p;
+        a = 1ll * a * a % p;
+        b >>= 1;
+    }
+
+    return res;
+}
+
+int main() {
+    std::ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    cin >> x >> t;
+
+    while (t--) {
+        cin >> n;
+
+        if (n == 1) {
+            cout << 2 << ' ' << 1 << endl;
+        } else if (x == 1) {
+            if (n % 2 == 1) {
+                cout << 0 << endl;
+            } else {
+                cout << 2 << ' ';
+
+                for (int i = 1; i <= n; i++) {
+                    cout << (i % 2 ? n - i + 1 : i - 1) << ' ';
+                }
+
+                cout << endl;
+            }
+        } else {  // x == 2
+            if (n == 2) {
+                cout << 2 << ' ' << "1 2" << endl;
+            } else if (n == 4) {
+                cout << 2 << ' ' << "1 3 2 4" << endl;
+            } else if (!is_prime(n)) {
+                cout << 0 << endl;
+            } else {
+                cout << 2 << ' ' << 1 << ' ';
+
+                for (int i = 2; i < n; i++) {
+                    cout << static_cast<long long>(i) * binpow(i - 1, n - 2, n) % n << ' ';
+                }
+
+                cout << n << endl;
+            }
+        }
+    }
+
+    return 0;
+}