#include <map>

#include <iostream>

#include <algorithm>

#include <utility>

using namespace std;

int main()

{

    map<float, float> map1 = { {,},{,},{,},{,},{,},{,},{,} };

    auto posKey = map1.find(3.0);

    if (posKey != map1.end())

    {

        cout << "" << posKey->first << "  " << posKey->second << endl;

    }

    auto posVal = find_if(map1.begin(),map1.end(),

        [](const pair<float, float>& elem1) {

            return elem1.second == 3.0;

        });

    if (posVal != map1.end())

    {

        cout << posVal->first << "   " << posVal->second << "" << endl;

    }

    system("pause");

    return ;

}