Update README

src/example.cc

@@ -0,0 +1,42 @@
+#include "roditty_zwick.h"
+
+#include <random>
+
+int main() {
+  graph::Digraph<std::uint16_t> G;
+  std::vector<std::pair<std::uint16_t, std::uint16_t>> dl_set;
+  std::vector<std::pair<std::uint16_t, std::uint16_t>> qr_set;
+  std::vector<std::pair<std::uint16_t, std::uint16_t>> in_set;
+  auto gen = std::bind(std::uniform_real_distribution<>(0, 1),
+                       std::default_random_engine());
+
+  for (int i = 0; i <= 100; ++i) {
+    for (int j = 0; j <= 100; ++j) {
+      auto rand = gen();
+      if (rand < 0.5) {
+        G.insert(i, j);
+        if (rand < 0.25)
+          dl_set.push_back({ i, j });
+        if (rand < 0.125)
+          qr_set.push_back({ i, j });
+      }
+    }
+  }
+
+  algo::HenzingerKing<std::uint16_t>* dr = new algo::HenzingerKing(G);
+  dr->init();
+
+  dr->remove(dl_set);
+
+  for (const auto& [u, v] : qr_set) {
+    if (dr->query(u, v))
+      ;
+    else
+      in_set.push_back({ u, v });
+  }
+
+  for (const auto& [u, v] : in_set)
+    dr->insert(u, { v });
+
+  return 0;
+}