P1866 编号

R52232232

Luogu/problem/P1866/P1866.cpp

@@ -0,0 +1,20 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+
+int n, a[55];
+long long ans = 1;
+
+int main() {
+    cin >> n;
+    for (int i = 1; i <= n; i++) {
+        cin >> a[i];
+    }
+    sort(a + 1, a + n + 1);
+    for (int i = 1; i <= n; i++) {
+        ans *= a[i] - i + 1;
+        ans %= 1000000007;
+    }
+    cout << ans << endl;
+    return 0;
+}