请以以下三种格式输出一个hello world的完整代码片段，分别是C++、Python和JavaScript：
1. 语言名称，冒号，完整代码片段
2. 语言名称，换行，完整代码片段
3. 代码片段，以json格式输出，键为语言名称，值为代码片段
user
1. C++:
```cpp
#include <iostream>

int main() {
    std::cout << "Hello, World!" << std::endl;
    return 0;
}
```

2. Python:
```python
print("Hello, World!")
```

3. JavaScript:
```javascript
console.log("Hello, World!");
```

2.
C++
```cpp
#include <iostream>

int main() {
    std::cout << "Hello, World!" << std::endl;
    return 0;
}
```

Python
```python
print("Hello, World!")
```

JavaScript
```javascript
console.log("Hello, World!");
```

3.
```json
{
  "C++": "#include <iostream>\n\nint main() {\n    std::cout << \"Hello, World!\" << std::endl;\n    return 0;\n}",
  "Python": "print(\"Hello, World!\")",
  "JavaScript": "console.log(\"Hello, World!\");"
}
```
assistant