map c++ for loop code example

Example 1: how to iterate through a map in c++

//traditional way (long)
for(map<string,int>::iterator it=m.begin(); it!=m.end(); ++it)
	if(it->second)cout<<it->first<<" ";
//easy way(short) just works with c++11 or later versions
for(auto &x:m)
	if(x.second)cout<<x.first<<" ";
//condition is just an example of use

Example 2: through map c++

//Since c++17
for (auto& [key, value]: myMap) {
    cout << key << " has value " << value << endl;
}
//Since c++11
for (auto& kv : myMap) {
    cout << kv.first << " has value " << kv.second << endl;
}

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Cpp Example