Add a lot more of my solutions.

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

CSES Problem Set/Mex Grid Construction.cpp

@@ -0,0 +1,134 @@
+/* Problem URL: https://cses.fi/problemset/task/3419 */
+
+#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 (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;
+    cin >> n;
+
+    vvi ans(n, vi(n));
+    ans[0][0] = 0;
+
+    V<V<set<int>>> mexleft(n, V<set<int>>(n));
+    V<V<set<int>>> mexup(n, V<set<int>>(n));
+    mexleft[0][0].insert(0);
+    mexup[0][0].insert(0);
+
+    auto find_mex = [](set<int> &a) {
+        int now = 0;
+        auto itr = a.begin();
+        
+        while (itr != a.end() && now == *itr) {
+            itr++;
+            now++;
+        }
+
+        return now;
+    };
+
+    rep(i, n) {
+        rep(j, n) {
+            if (i == 0 && j == 0) {
+                continue;
+            }
+
+            if (i > 0) {
+                swap(mexup[i][j], mexup[i - 1][j]);
+            }
+
+            if (j > 0) {
+                swap(mexleft[i][j], mexleft[i][j - 1]);
+            }
+
+            set<int> tmp;
+            repv(k, mexup[i][j]) {
+                tmp.insert(k);
+            }
+            repv(k, mexleft[i][j]) {
+                tmp.insert(k);
+            }
+
+            int mex = find_mex(tmp);
+            ans[i][j] = mex;
+            mexup[i][j].insert(mex);
+            mexleft[i][j].insert(mex);
+        }
+    }
+
+    rep(i, n) {
+        rep(j, n) {
+            cout << ans[i][j] << " \n"[j == n - 1];
+        }
+    }
+}