Adds cpp demo.

demos/cpp/.gitignore

@@ -0,0 +1 @@
+main

demos/cpp/.vscode/launch.json

@@ -0,0 +1,29 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "name": "g++ build and debug active file",
+            "type": "cppdbg",
+            "request": "launch",
+            "program": "${fileDirname}/${fileBasenameNoExtension}",
+            "args": [],
+            "stopAtEntry": false,
+            "cwd": "${workspaceFolder}",
+            "environment": [],
+            "externalConsole": false,
+            "MIMode": "gdb",
+            "setupCommands": [
+                {
+                    "description": "Enable pretty-printing for gdb",
+                    "text": "-enable-pretty-printing",
+                    "ignoreFailures": true
+                }
+            ],
+            "preLaunchTask": "g++ build active file",
+            "miDebuggerPath": "/usr/bin/gdb"
+        }
+    ]
+}

demos/cpp/.vscode/tasks.json

@@ -0,0 +1,25 @@
+{
+    // See https://go.microsoft.com/fwlink/?LinkId=733558 
+    // for the documentation about the tasks.json format
+    "version": "2.0.0",
+    "tasks": [
+        {
+            "type": "shell",
+            "label": "g++ build active file",
+            "command": "/usr/bin/g++",
+            "args": [
+                "-g",
+                "${file}",
+                "-o",
+                "${fileDirname}/${fileBasenameNoExtension}"
+            ],
+            "options": {
+                "cwd": "/usr/bin"
+            },
+            "problemMatcher": [
+                "$gcc"
+            ],
+            "group": "build"
+        }
+    ]
+}

demos/cpp/main.cpp

@@ -0,0 +1,14 @@
+#include <iostream>
+#include <vector>
+#include <string>
+
+using namespace std;
+
+int main()
+{
+    // visualize `myGraphJson`!
+    string myGraphJson = "{\"kind\":{\"graph\":true},"
+        "\"nodes\":[{\"id\":\"1\"},{\"id\":\"2\"}],"
+        "\"edges\":[{\"from\":\"1\",\"to\":\"2\"}]}";
+    cout << myGraphJson;
+}

extension/README.md

@@ -16,6 +16,7 @@ See [demos](./demos/) for demos. These languages and debuggers are verified to w
 -   C# using `coreclr` debug adapter: ✅ Rudimentary Support
 -   PHP using `php` debug adapter: ✅ Rudimentary Support
 -   Java using `java` debug adapter: ✅ Rudimentary Support
+-   C++ using `cppdbg` debug adapter: ✅ Rudimentary Support
 
 All other languages and debuggers might work too.