首先调用f的模板化版本，第一个参数的类型是字符串，作为大小可变的参数提供字符和双精度值。

The first time around, the templated version of f is called, with a string as the first argument type, and the character and double are packed off as the variable size argument.

youdao

首先调用f的模板化版本，第一个参数的类型是字符串，作为大小可变的参数提供字符和双精度值。

The first time around, the templated version of f is called, with a string as the first argument type, and the character and double are packed off as the variable size argument.

youdao