add/fix tests

geometry/sort_by_argument.hpp

@@ -1,24 +1,26 @@
 #pragma once
-#include <cmath>
 
-// CUT begin
 // Point on grid, sortable by its argument
 struct Point {
-    constexpr static double eps = 1e-2;
     long long X, Y;
-    double theta;
     Point() = default;
-    Point(long long x, long long y) : X(x), Y(y), theta(std::atan2(y, x)) {}
+    Point(long long x, long long y) : X(x), Y(y) {}
+
     bool operator<(const Point &r) const {
-        double b = theta - r.theta;
-        return std::abs(b) > eps ? (b < 0) : (X * r.Y > r.X * Y);
+        const int ll = lower_or_upper(), lr = r.lower_or_upper();
+        if (ll != lr) return ll < lr;
+        return X * r.Y > r.X * Y;
     }
+
     bool operator==(const Point &r) const {
-        return std::abs(theta - r.theta) < eps and X * r.Y == r.X * Y;
+        return lower_or_upper() == r.lower_or_upper() and X * r.Y == r.X * Y;
     }
-    void rotate_pi() {
-        theta += M_PI;
-        X *= -1;
-        Y *= -1;
+
+    int lower_or_upper() const {
+        if (Y) return Y > 0 ? 1 : -1;
+        if (X) return X > 0 ? -1 : 1;
+        return 0; // origin
     }
+
+    void rotate_pi() { X = -X, Y = -Y; }
 };

geometry/test/sort_by_argument.test.cpp

@@ -1,8 +1,9 @@
+#define PROBLEM "https://judge.yosupo.jp/problem/sort_points_by_argument"
 #include "geometry/sort_by_argument.hpp"
+
 #include <algorithm>
 #include <iostream>
 #include <vector>
-#define PROBLEM "https://judge.yosupo.jp/problem/sort_points_by_argument"
 using namespace std;
 
 int main() {

random/rand_nondeterministic.hpp

@@ -5,6 +5,7 @@
 struct rand_int_ {
     using lint = long long;
     std::mt19937 mt;
+    // rand_int_() : mt(42) {}
     rand_int_() : mt(std::chrono::steady_clock::now().time_since_epoch().count()) {}
     lint operator()(lint x) { return this->operator()(0, x); } // [0, x)
     lint operator()(lint l, lint r) {

unionfind/test/potentialized_unionfind_modint.test.cpp

@@ -0,0 +1,38 @@
+#define PROBLEM "https://judge.yosupo.jp/problem/unionfind_with_potential"
+
+#include "../potentialized_unionfind.hpp"
+
+#include <iostream>
+using namespace std;
+
+#include <atcoder/modint>
+using mint = atcoder::modint998244353;
+
+int main() {
+    cin.tie(nullptr), ios::sync_with_stdio(false);
+
+    int N, Q;
+    cin >> N >> Q;
+    PotentializedUnionFind<mint> uf(N);
+
+    while (Q--) {
+        int t, u, v;
+        cin >> t >> u >> v;
+        if (t == 0) {
+            int x;
+            cin >> x;
+            if (uf.same(u, v) and uf.diff(v, u) != x) {
+                cout << "0\n";
+            } else {
+                cout << "1\n";
+                uf.unite(v, u, x);
+            }
+        } else {
+            if (uf.same(u, v)) {
+                cout << uf.diff(v, u).val() << '\n';
+            } else {
+                cout << "-1\n";
+            }
+        }
+    }
+}