// map::find

#include <iostream>

#include <map>

#include <vector>

//#include <pair>

using namespace std;

struct MeasUpdateVariables

{

vector<int> datas;

char c;

unsigned int dim;

MeasUpdateVariables(unsigned int d):dim(d){datas.resize(dim);std::cout<<dim<<endl;}

}; //struct

int main ()

{

std::map<char,int> mymap;

std::map<char,int>::iterator it;

mymap['a']=50;

mymap['b']=100;

mymap['c']=150;

mymap['d']=200;

it = mymap.find('b');

if (it != mymap.end())

mymap.erase (it);

// print content:

std::cout << "elements in mymap:" << '\n';

std::cout << "a => " << mymap.find('a')->second << '\n';

std::cout << "c => " << mymap.find('c')->second << '\n';

std::cout << "d => " << mymap.find('d')->second << '\n';

std::map<unsigned int, MeasUpdateVariables> _mapMeasUpdateVariables;

std::map<unsigned int, MeasUpdateVariables>::iterator _mapMeasUpdateVariables_it;

vector<unsigned int> meas_dimensions;

meas_dimensions.push_back(1);

meas_dimensions.push_back(6);

meas_dimensions.push_back(3);

unsigned int meas_dimension;

for(int i = 0 ; i< meas_dimensions.size(); i++)

{

// find if variables with size meas_sizes[i] are already allocated

meas_dimension = meas_dimensions[i];

_mapMeasUpdateVariables_it = _mapMeasUpdateVariables.find(meas_dimension);

if( _mapMeasUpdateVariables_it == _mapMeasUpdateVariables.end())

{

//variables with size z.rows() not allocated yet

_mapMeasUpdateVariables_it = (_mapMeasUpdateVariables.insert

(std::pair<unsigned int, MeasUpdateVariables>( meas_dimension,MeasUpdateVariables(meas_dimension) ))).first;

}

}

meas_dimensions.push_back(16);

meas_dimensions.push_back(31);

for(int i = 0 ; i< meas_dimensions.size(); i++)

{

// find if variables with size meas_sizes[i] are already allocated

meas_dimension = meas_dimensions[i];

_mapMeasUpdateVariables_it = _mapMeasUpdateVariables.find(meas_dimension);

if( _mapMeasUpdateVariables_it == _mapMeasUpdateVariables.end())

{

//variables with size z.rows() not allocated yet

_mapMeasUpdateVariables_it = (_mapMeasUpdateVariables.insert

(std::pair<unsigned int, MeasUpdateVariables>( meas_dimension,MeasUpdateVariables(meas_dimension) ))).first;

}

}

// std::map<char,int> mymap;

// first insert function version (single parameter):

mymap.insert ( std::pair<char,int>('a',100) );

mymap.insert ( std::pair<char,int>('z',200) );

std::pair<std::map<char,int>::iterator,bool> ret;

ret = mymap.insert ( std::pair<char,int>('z',500) );

if (ret.second==false) {

std::cout << "element 'z' already existed";

std::cout << " with a value of " << ret.first->second << '\n';

}

return 0;

}