C++/Map Multimap/map erase

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Erase a found pair from map

  
 
#include <iostream>
#include <map>
#include <string>
using namespace std;
int main( ) {
   map<string, string> strMap;
   strMap["Monday"]    = "1";
   strMap["Tuesday"]   = "2";
   strMap["Wednesday"] = "3";
   strMap["Thursday"]  = "4";
   strMap["Friday"]    = "5";
   strMap["Saturday"]  = "6";
   strMap.insert(pair<string, string>("Sunday", "7"));
   strMap.erase(strMap.find("Tuesday"));
   for (map<string, string>::iterator p = strMap.begin( );
      p != strMap.end( ); ++p ) {
         cout << "English: " << p->first<< ", #: " << p->second << endl;
   }
   cout << endl;
}
 /* 
English: Friday, #: 5
English: Monday, #: 1
English: Saturday, #: 6
English: Sunday, #: 7
English: Thursday, #: 4
English: Wednesday, #: 3

 */


map erase

  
#include <map>
#include <iostream>
using namespace std;
class Data
{
public:
  Data(int val = 0) { mVal = val; }
  int getVal() const { return mVal; }
  void setVal(int val) {mVal = val; }
protected:
  int mVal;
};
int main(int argc, char** argv)
{
  map<int, Data> dataMap;
  dataMap[1] = Data(4);
  cout << "There are " << dataMap.count(1) << " elements with key 1\n";
  dataMap.erase(1);
  cout << "There are " << dataMap.count(1) << " elements with key 1\n";
  return (0);
}


Remove an entry from a map

  
 
/* The following code example is taken from the book
 * "The C++ Standard Library - A Tutorial and Reference"
 * by Nicolai M. Josuttis, Addison-Wesley, 1999
 *
 * (C) Copyright Nicolai M. Josuttis 1999.
 * Permission to copy, use, modify, sell and distribute this software
 * is granted provided this copyright notice appears in all copies.
 * This software is provided "as is" without express or implied
 * warranty, and with no claim as to its suitability for any purpose.
 */
#include <iostream>
#include <map>
#include <string>
using namespace std;
int main()
{
    /* create map / associative array
     * - keys are strings
     * - values are floats
     */
    typedef map<string,float> StringFloatMap;
    StringFloatMap stocks;      // create empty container
    // insert some elements
    stocks["BASF"] = 369.50;
    stocks["VW"] = 413.50;
    stocks["Daimler"] = 819.00;
    stocks["BMW"] = 834.00;
    stocks["Siemens"] = 842.20;
    // print all elements
    StringFloatMap::iterator pos;
    for (pos = stocks.begin(); pos != stocks.end(); ++pos) {
        cout << "stock: " << pos->first << "\t"
             << "price: " << pos->second << endl;
    }
    cout << endl;

    stocks.erase("VW");
    // print all elements
    for (pos = stocks.begin(); pos != stocks.end(); ++pos) {
        cout << "stock: " << pos->first << "\t"
             << "price: " << pos->second << endl;
    }
    cout << endl;
}
 /* 
stock: BASF     price: 369.5
stock: BMW      price: 834
stock: Daimler  price: 819
stock: Siemens  price: 842.2
stock: VW       price: 413.5
stock: BASF     price: 369.5
stock: BMW      price: 834
stock: Daimler  price: 819
stock: Siemens  price: 842.2

 */