Update 10.2.concepts.cpp

[lakshita157]

resolve #issue_id

Description

Please describe the motivation of this pull request, and what problem was solved in this PR.

Change List

• Fix typo error of XXX
• Add description regarding XXX feature
• Resolve error content of XXX

Reference

Please add reference if necessary

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说明

此处详细说明 PR 的动机是什么、解决了什么样的问题。

变化箱单

• 修复了 XXX 的 typo 错误
• 增加了 XXX 相关的说明
• 解决了关于 XXX 的描述性错误

参考文献

如果有请注明

[frederick-vs-ja]

We shouldn't use non-standard headers, which are the implementation details of the standard library and not portable, when standard headers are available.

[changkun]

Thanks but non-std content is not intended to be part of the book