c-将std :: map复制到对的std :: vector中

我正在尝试将地图复制到向量对中,因此可以根据向量对中的第二个数据成员对向量进行排序.我已经这样解决了：

void mappedWordsListSorter(){
  for (auto itr = mappedWordsList.begin(); itr != mappedWordsList.end(); ++itr){
    vectorWordsList.push_back(*itr);
  }
  sort(vectorWordsList.begin(), vectorWordsList.end(), [=](pair<string, int>& a, pair<string, int>& b){return a.second > b.second;});
}

我需要找到一种方法,而不使用原始循环,而是使用标准库.我遇到了很多仅通过传递键或映射值来执行此操作的示例.我需要复制成对的向量 最佳答案

只需使用std :: vector的assign成员函数即可.

//no need to call reserve, bidirectional iterators or better will compute the size and reserve internally.
vectorWordsList.assign(mappedWordsList.begin(), mappedWordsList.end());

如果向量中已有要覆盖的值,请改用insert

vectorWordsList.reserve(vectorWordsList.size() + mappedWordsList.size()); // make sure we only have a single memory allocation
vectorWordsList.insert(vectorWordsList.end(), mappedWordsList.begin(), mappedWordsList.end());

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转载注明原文：c-将std :: map复制到对的std :: vector中 - 代码日志

解决方法:

只需使用std :: vector的assign成员函数即可.

//no need to call reserve, bidirectional iterators or better will compute the size and reserve internally.
vectorWordsList.assign(mappedWordsList.begin(), mappedWordsList.end());

如果向量中已有要覆盖的值,请改用insert

vectorWordsList.reserve(vectorWordsList.size() + mappedWordsList.size()); // make sure we only have a single memory allocation
vectorWordsList.insert(vectorWordsList.end(), mappedWordsList.begin(), mappedWordsList.end());

标签：std-pair,c,stdvector,c-standard-library,stdmap
来源： https://codeday.me/bug/20191010/1886554.html