Use subscript to change the value in a map : map subscript indexer « map multimap « C++ Tutorial

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C++ Tutorial » map multimap » map subscript indexer 
23.8.1.Use subscript to change the value in a map
#include <iostream>
using std::cout;
using std::endl;

#include <map> // map class-template definition

int main()
{
   std::map< int, double, std::less< int > > pairs;

   pairs.insertstd::map< int, double, std::less< int > >::value_type152.7 ) );
   pairs.insertstd::map< int, double, std::less< int > >::value_type30111.11 ) );
   pairs.insertstd::map< int, double, std::less< int > >::value_type01010.1 ) );
   pairs.insertstd::map< int, double, std::less< int > >::value_type1022.22 ) );
   pairs.insertstd::map< int, double, std::less< int > >::value_type2533.333 ) );
   pairs.insertstd::map< int, double, std::less< int > >::value_type077.54 ) )// dup ignored
   pairs.insertstd::map< int, double, std::less< int > >::value_type209.345 ) );
   pairs.insertstd::map< int, double, std::less< int > >::value_type1599.3 ) )// dup ignored

   cout << "pairs contains:\nKey\tValue\n";

   // use const_iterator to walk through elements of pairs
   for std::map< int, double, std::less< int > >::const_iterator iter = pairs.begin();
      iter != pairs.end(); ++iter )
      cout << iter->first << '\t' << iter->second << '\n';

   pairs25 9999.99// use subscripting to change value for key 25

   cout << "\n\n\n";

   // use const_iterator to walk through elements of pairs
   for std::map< int, double, std::less< int > >::const_iterator iter = pairs.begin();
      iter != pairs.end(); ++iter )
      cout << iter->first << '\t' << iter->second << '\n';



   cout << endl;
   return 0;
}
pairs contains:
Key     Value
0       1010.1
10      22.22
15      2.7
20      9.345
25      33.333
30      111.11



0       1010.1
10      22.22
15      2.7
20      9.345
25      9999.99
30      111.11
23.8.map subscript indexer
23.8.1.Use subscript to change the value in a map
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