Add a lot more of my solutions.

I don't remember which ones doesn't pass though

CSES Problem Set/Giant Pizza.cpp

@@ -0,0 +1,207 @@
+/* Problem URL: https://cses.fi/problemset/task/1684 */
+
+#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;
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    int n, m;
+    cin >> m >> n;
+
+    n <<= 1;
+
+    vvi graph(n);
+    vvi inv(n);
+
+    while (m--) {
+        char op1, op2;
+        int a, b;
+        cin >> op1 >> a >> op2 >> b;
+
+        a--, b--;
+
+        if (op1 == '-') {
+            a += n >> 1;
+        }
+
+        if (op2 == '-') {
+            b += n >> 1;
+        }
+
+        graph[a].push_back((b + (n >> 1)) % n);
+        graph[b].push_back((a + (n >> 1)) % n);
+        inv[(b + (n >> 1)) % n].push_back(a);
+        inv[(a + (n >> 1)) % n].push_back(b);
+    }
+
+    V<bool> vis(n);
+    vi top;
+
+    function<void(int)> preorder = [&](int i) {
+        vis[i] = true;
+
+        for (auto j : graph[i]) {
+            if (vis[j]) {
+                continue;
+            }
+
+            preorder(j);
+        }
+
+        top.push_back(i);
+    };
+
+    rep(i, n) {
+        if (vis[i]) {
+            continue;
+        }
+
+        preorder(i);
+    }
+
+    reverse(all(top));
+    fill(all(vis), false);
+
+    vi group(n);
+    vi representant(n);
+    int g = 0;
+
+    function<void(int)> scc = [&](int i) {
+        vis[i] = true;
+        group[i] = g;
+
+        for (auto j : inv[i]) {
+            if (vis[j]) {
+                continue;
+            }
+
+            scc(j);
+        }
+    };
+
+    repv(i, top) {
+        if (vis[i]) {
+            continue;
+        }
+
+        scc(i);
+        representant.push_back(i);
+        g++;
+    }
+
+    rep(i, n >> 1) {
+        if (group[i] == group[i + (n >> 1)]) {
+            cout << "IMPOSSIBLE\n";
+            return 0;
+        }
+    }
+
+    fill(all(vis), false);
+    reverse(all(representant));
+
+    string ans(n >> 1, ' ');
+
+    function<void(int)> getans = [&](int i) {
+        vis[i] = true;
+
+        if (ans[i % (n >> 1)] == ' ') {
+            ans[i % (n >> 1)] = i < (n >> 1) ? '-' : '+';
+        }
+
+        repv(j, graph[i]) {
+            if (vis[j] || group[j] != group[i]) {
+                continue;
+            }
+
+            getans(j);
+        }
+    };
+
+    repv(i, representant) {
+        if (vis[i]) {
+            continue;
+        }
+
+        getans(i);
+    }
+
+    repv(i, ans) {
+        cout << i << ' ';
+    }
+    cout << '\n';
+}