Using a vector of unsigned chars in a map [closed] - c++

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I need help using unsigned chars in std::vectors that are inside of a std::map.
This is how I declare the std::map:
std::map<int, std::vector<unsigned char>> DataMap;
The problem comes when I try to assign a std::vector to the std::map.
it->first comes from another std::map, as this code is inside a loop.
std::vector<unsigned char> charHolder;
for(int i = 0; i < 10; i++)
{
charHolder.push_back('2');
}
DataMap.insert(std::pair<int, std::vector<unsigned char>(it->first, charHolder));
The errors:
Template argument 2 is invalid
I need to assigned a char[] array to the 2 place in the std::map. I've tried an array, but I had no luck.

Answer 1

You are missing a > character
DataMap.insert (std::pair<int, std::vector<unsigned char>>(it->first, charHolder));
^
You may use uniform initializer as following:
DataMap.insert ({it->first, charHolder});

Answer 2

Some of the many fun and varied ways to get data into a map:
std::map<int, std::vector<unsigned char>> DataMap;
void add(int i, std::vector<unsigned char> v)
{
// efficient move versions
DataMap.emplace(i, std::move(v));
DataMap[i] = std::move(v);
DataMap.insert(std::make_pair(i, std::move(v)));
DataMap.emplace(std::piecewise_construct,
std::make_tuple(i),
std::forward_as_tuple(std::move(v)));
// less efficient copy versions
DataMap.emplace(i, v);
DataMap[i] = v;
DataMap.insert(std::make_pair(i, v));
DataMap.emplace(std::piecewise_construct,
std::make_tuple(i),
std::make_tuple(v));
}