What is the difference between printf and cout in C++?

printf and cout are two different ways of outputting in C++, with the main differences being:

1. In C language, printf is the output function that requires including a header file and specifying the output format using a formatted string. In C++, cout is the output stream that also requires including a header file and outputting data using the << operator.
2. Type safety: printf does not perform type checking when outputting and requires manually specifying the output format. However, cout performs type inference when outputting, allowing for direct output of different data types, with the compiler automatically selecting the appropriate output method based on the data type.
3. Readability: printf requires manually specifying the output format in the formatting string, making it difficult to understand especially for complex outputs. In contrast, cout uses an object-oriented approach by chaining the output operator << with the data to be outputted, resulting in cleaner and more readable code.
4. Scalability: printf requires manually specifying the format for each output, which may differ for different data types, while cout can customize the output format by overloading the << operator, making the output more flexible.

In conclusion, there are certain differences between printf and cout in terms of syntax, type safety, readability, and extensibility. In C++, it is recommended to use cout for output operations, especially when needing to output different types of data, as it is more convenient and secure.