Stxxl map with std::string as key and std::vector as value

问题

I need a large map of sets of numbers. So i'm using stxxl and it's basically something like map<std::string, std::vector<int>>. The key is 3-letters identifier. There are about 3k enteries in the map, and each of them can contain up to 500K numbers. It is important to use vector in the value since i need to change it (add/remove numbers).

The problem is that after i insert all my data, when i try to access an element in the map, the vector is currupted.

#define MAX_STRING_IN_MAP    ("ZZZZZZZ")

// String comparator.
struct CompareGreaterString
{
    bool operator () (const std::string& a, const std::string& b) const {
        return a > b; 
    }
    static std::string max_value() {
        return MAX_STRING_IN_MAP; 
    }
};
typedef stxxl::map<std::string, std::vector<int>, CompareGreaterString, DATA_NODE_BLOCK_SIZE, DATA_LEAF_BLOCK_SIZE> myMap;

...
ifstream input_file;
myMap map((mapBacteria::node_block_type::raw_size) * 5, (mapBacteria::leaf_block_type::raw_size) * 5);
...

unsigned int count = 0;
while (count < max_number) {
    count++;
    std::string name;
    unsigned int length;
    input_file >> name;
    input_file >> length;
    std::vector<int> iterationGroup = readNumbers(input_file);
    myMap.insert(std::pair<std::string, std::vector<int>>(name, iterationGroup));
    // If i am trying to access the data here, like this:
    // auto result = myMap[name];
    // It seems perfectely fine.
}

For example, if after the above insertion i will try to access the map:

auto result = myMap["aaa"];

Then i get a vector with the right size, but all it's elements have a value of 0xfeeefeee instead of the numbers that were originally in the inserted vector.

来源：https://stackoverflow.com/questions/32795337/stxxl-map-with-stdstring-as-key-and-stdvector-as-value

标签

c++

vector

stl

stxxl