c++ - How can I find out if a map contains a given value? -


i'd find out whether given value present in map. getting corresponding key(s) nice not required.

bool map::contains(string value);

is there simple way other iterate on whole map , comparing each value given value? why there no corresponding method in stl?

std::map indexes elements key; not index them value. therefore, there no way element value without iterating on map.

take @ boost.bimap:

boost.bimap bidirectional maps library c++. boost.bimap can create associative containers in both types can used key. bimap<x,y> can thought of combination of std::map<x,y> , std::map<y,x>.

using pretty straightforward, although of course need consider question of whether duplicate values allowed.

also, see is there boost.bimap alternative in c++11?


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