#13363. 「NOIP2022模拟赛zzq」Divisor

http://www.nfls.com.cn:10611/submission/243821

NFLSOJ/13363/13363.cpp

@@ -0,0 +1,74 @@
+#include <iostream>
+#include <cmath>
+#include <fstream>
+#include <functional>
+#include <utility>
+#include <vector>
+
+// using std::cin;
+// using std::cout;
+std::ifstream cin("divisor.in");
+std::ofstream cout("divisor.out");
+const char endl = '\n';
+
+int main() {
+    std::ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    int t;
+
+    cin >> t;
+
+    while (t--) {
+        int n;
+
+        cin >> n;
+
+        int x = n, lst = 0;
+        std::vector<std::pair<int, int>> a;
+        std::vector<int> ans;
+
+        for (int i = 2; i * i <= x; i++) {
+            if (x % i == 0) {
+                int cnt = 0;
+
+                while (x % i == 0) x /= i, cnt++;
+
+                a.emplace_back(i, cnt);
+            }
+        }
+
+        if (x > 1) a.emplace_back(x, 1);
+
+        std::function<void(int, int)> dfs = [&](int p, int x) -> void {
+            if (p == a.size()) {
+                ans.emplace_back(lst = x);
+
+                return;
+            }
+
+            if (lst % a[p].first) {
+                for (int i = 0; i <= a[p].second; i++) {
+                    dfs(p + 1, x);
+                    x *= a[p].first;
+                }
+            } else {
+                x *= std::pow(a[p].first, a[p].second);
+                for (int i = 0; i <= a[p].second; i++) {
+                    dfs(p + 1, x);
+                    x /= a[p].first;
+                }
+            }
+        };
+
+        dfs(0, 1);
+
+        cout << ans.size() << endl;
+
+        for (int x : ans) cout << x << ' ';
+
+        cout << endl;
+    }
+
+    return 0;
+}