add Chapter02 examples

Chapter02/vector_pmr.cpp

@@ -0,0 +1,34 @@
+#include <array>
+#include <cstdio>
+#include <cstdlib>
+#include <memory_resource>
+#include <new>
+#include <vector>
+
+void *operator new(std::size_t count, std::align_val_t al) {
+  printf("%s, size = %ld\r\n", __PRETTY_FUNCTION__, count);
+  return std::malloc(count);
+}
+
+int main() {
+  using namespace std;
+  using namespace std::pmr;
+
+  constexpr size_t n_elem = 8;
+  array<uint8_t, sizeof(uint8_t) * 8> buffer{0};
+  monotonic_buffer_resource mbr{buffer.data(), buffer.size()};
+  polymorphic_allocator<uint8_t> pa{&mbr};
+  std::pmr::vector<uint8_t> vec{pa};
+  // vec.reserve(n_elem);
+  //
+  for (uint8_t i = 0; i < n_elem; i++) {
+    vec.push_back(i);
+  }
+
+  for (uint8_t data : buffer) {
+    printf("%d ", data);
+  }
+  printf("\r\n");
+
+  return 0;
+}