add Chapter02 examples

Chapter02/vector_dyn_mem.cpp

@@ -0,0 +1,30 @@
+#include <cstdint>
+#include <cstdio>
+#include <cstdlib>
+#include <vector>
+
+void *operator new(std::size_t count) {
+  printf("%s, size = %ld\r\n", __PRETTY_FUNCTION__, count);
+  return std::malloc(count);
+}
+
+void operator delete(void *ptr) noexcept {
+  printf("%s\r\n", __PRETTY_FUNCTION__);
+  std::free(ptr);
+}
+
+int main() {
+  std::vector<std::uint8_t> vec;
+  constexpr std::size_t n_elem = 8;
+  for (std::uint8_t i = 0; i < n_elem; i++) {
+    vec.push_back(i);
+  }
+  const auto print_array = [](uint8_t *arr, std::size_t n) {
+    for (std::size_t i = 0; i < n; i++) {
+      printf("%d ", arr[i]);
+    }
+    printf("\r\n");
+  };
+  print_array(vec.data(), n_elem);
+  return 0;
+}