Add a bunch of other problems.

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Codeforces Round 560 (Div. 3)/D. Almost All Divisors.cpp

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+/* Problem URL: https://codeforces.com/problemset/problem/1165/D */
+
+/* what? */
+#include <bits/stdc++.h>
+
+using namespace std;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (size_t i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (size_t i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    vi check(1e6 + 1);
+    for (size_t i = 1; i <= 1e6; i++) {
+        check[i] = i;
+    }
+
+    check[1] = 0;
+
+    vi primes;
+
+    for (size_t i = 2; i <= 1e6; i++) {
+        if (check[i] != i) {
+            continue;
+        }
+
+        primes.push_back(i);
+
+        for (size_t j = i * 2; j <= 1e6; j += i) {
+            check[j] = i;
+        }
+    }
+
+    int t;
+    cin >> t;
+    while (t--) {
+        int n;
+        cin >> n;
+
+        if (n == 1) {
+            ll num;
+            cin >> num;
+            if (check[num] != num) {
+                cout << "-1\n";
+                continue;
+            }
+            cout << num * num << '\n';
+            continue;
+        }
+
+        vl nums(n);
+        cin >> nums;
+        sortv(nums);
+
+        ll num = nums.back() * nums.front();
+        ll ans = num;
+
+        bool pos = true;
+
+        for (auto i : nums) {
+            if (num % i != 0) {
+                pos = false;
+                break;
+            }
+        }
+
+        if (!pos) {
+            cout << "-1\n";
+            continue;
+        }
+
+        int count = 1;
+        for (size_t i = 0; primes[i] * primes[i] * primes[i] <= num; i++) {
+            int c = 0;
+            while (num % primes[i] == 0) {
+                c++;
+                num /= primes[i];
+            }
+
+            count *= c + 1;
+        }
+
+        if (check[num] == num) {
+            count *= 2;
+        } else if (floor(sqrt(num)) * floor(sqrt(num)) == num && check[sqrt(num)] == floor(sqrt(num))) {
+            count *= 3;
+        } else if (num != 1) {
+            count *= 4;
+        }
+
+        cout << (count - 2 == nums.size() ? ans : -1) << '\n';
+    }
+}