Add a bunch of other problems.

Testing Round 20 (Unrated, Communication Problems)/C. Intercepting Butterflies.cpp

@@ -0,0 +1,181 @@
+/* Problem URL: https://codeforces.com/contest/2168/problem/C */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int 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;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 1
+
+void solve1()
+{
+    int x;
+    cin >> x;
+    x--;
+
+    int xo = 0;
+    set<int> all;
+    rep(i, 15) {
+        int bit = (x >> i) & 1;
+        if (bit) {
+            all.insert(i + 1);
+            xo ^= i + 1;
+        }
+    }
+
+    int pa = __builtin_popcount(xo) & 1;
+    rep(j, 4) {
+        if ((xo >> j) & 1) {
+            all.insert(j + 16);
+        }
+    }
+
+    if (pa) {
+        all.insert(20);
+    }
+
+    cout << all.size() << '\n';
+    repv(i, all) {
+        cout << i << ' ';
+    }
+    cout << '\n';
+}
+
+void solve2()
+{
+    int n;
+    cin >> n;
+
+    int act = 0;
+    int xo = 0;
+    int tmp = 0;
+    int pa = 0;
+    rep(i, n) {
+        int bit;
+        cin >> bit;
+        if (bit <= 15) {
+            act |= (1 << (bit - 1));
+            tmp ^= bit;
+            continue;
+        }
+
+        if (bit < 20) {
+            xo |= (1 << (bit - 16));
+            continue;
+        }
+
+        pa = 1;
+    }
+
+    if ((__builtin_popcount(xo) & 1) != pa) {
+        cout << act + 1 << '\n';
+        return;
+    }
+
+    if ((tmp ^ xo) == 0) {
+        cout << act + 1 << '\n';
+        return;
+    }
+
+    act ^= 1 << ((tmp ^ xo) - 1);
+    cout << act + 1 << '\n';
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    string op;
+    cin >> op;
+    bool c = op[0] != 'f';
+
+    void (*solve[])() = {solve1, solve2};
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve[c]();
+    }
+}