add Chapter01 examples

Chapter01/undefined_behavior.cpp

@@ -0,0 +1,16 @@
+#include <cstdio>
+#include <limits>
+
+int foo(int x) {
+  int y = x + 1;
+  return y > x;
+}
+
+int main() {
+  if (foo(std::numeric_limits<int>::max())) {
+    printf("X is larger than X + 1\r\n");
+  } else {
+    printf("X is NOT larger than X + 1. Oh nooo !\r\n");
+  }
+  return 0;
+}