URGENT: iterating through Hash Table

I have an STL hashTable keyed on strings and the objects are custom objects.  What is the best way to go and get each pair (I need to ouptut both the key and value together).
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jjacksnAsked:
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nil_dibCommented:
sample for map (hashTable should be similar) :

#pragma warning(disable:4786)

#include <iostream>
#include <string>
#include <map>

using namespace std ;

typedef map<string, int> STRING2INT;

void main()
{
    STRING2INT MyMap;
    STRING2INT::iterator MyIterator;
    string MyBuffer;

    // print the maximum number of <key,data> pairs that MyMap can hold
    cout << "MyMap is capable of holding " << MyMap.max_size()
         << " <string,int> pairs" << endl;

    if(!MyMap.empty())
        cout << "MyMap has " << MyMap.size() << " entries" << endl;
    else
        cout << "MyMap is empty" << endl;
        cout << "Entering new entries in MyMap" << endl;
    // Fill in MyMap with the months of the year, mapped to their number
    // January - 1, February - 2, etc. using operator[].
    MyMap["January"] = 1;
    MyMap["February"] = 2;
    MyMap["March"] = 3;
    MyMap["April"] = 4;
    MyMap["May"] = 5;
    MyMap["June"] = 6;
    MyMap["July"] = 7;
    MyMap["August"] = 8;
    MyMap["September"] = 9;
    MyMap["October"] = 10;
    MyMap["November"] = 11;
    MyMap["December"] = 12;

    if(!MyMap.empty())
        cout << "MyMap has " << MyMap.size() << " entries" << endl;
    else
        cout << "MyMap is empty" << endl;

    // Ask the user for a month of the year and print the number
    // that corresponds to the month entered
    //MyIterator = MyMap.end();
    while(MyIterator == MyMap.end()){
        cout << "Enter a Month :";
        cin >> MyBuffer;
        if((MyIterator = MyMap.find(MyBuffer)) != MyMap.end())
            cout << (*MyIterator).first << " is Month Number "
                 << (*MyIterator).second << endl;
        else
            cout << "Enter a Valid Month (example: March)" << endl;
    }

    // empty MyMap - note that clear simply calls erase(begin(),end());
    MyMap.clear();

    if(!MyMap.empty())
        cout << "MyMap has " << MyMap.size() << " entries" << endl;
    else
        cout << "MyMap is empty" << endl;
        cout << "Entering new entries in MyMap" << endl;
    // Fill MyMap with the days of the week, each mapped to an int
    MyMap["Monday"] = 1;
    MyMap["Tuesday"] = 2;
    MyMap["Wednesday"] = 3;
    MyMap["Thursday"] = 4;
    MyMap["Friday"] = 5;
    MyMap["Saturday"] = 6;
    MyMap["Sunday"] = 7;

    if(!MyMap.empty())
        cout << "MyMap has " << MyMap.size() << " entries" << endl;
    else
        cout << "MyMap is empty" << endl;

    // Ask the user for a day of the week and print the number
    // that corresponds to the day entered
    MyIterator = MyMap.end();
    while(MyIterator == MyMap.end()){
        cout << "Enter a Day of the Week:";
        cin >> MyBuffer;
        if((MyIterator = MyMap.find(MyBuffer)) != MyMap.end())
            cout << (*MyIterator).first << " is Day Number "
                 << (*MyIterator).second << endl;
        else
            cout <<"Enter a Valid Day of the Week(example: Monday)"<< endl;
    }
// Now clear MyMap again - this time using erase instead of clear
    MyMap.erase(MyMap.begin(), MyMap.end());

    if(!MyMap.empty())
        cout << "MyMap has " << MyMap.size() << " entries" << endl;
    else
        cout << "MyMap is empty" << endl;

}



nil_dib
0
jjacksnAuthor Commented:
am I correct in thinking that If I make an iterator, .first will contain the key and .second will contain the value?
0
nil_dibCommented:
no! look at this sample:

#pragma warning(disable:4786)

#include <iostream>
#include <string>
#include <map>

using namespace std;


typedef map<int, string, less<int> > INT2STRING;

void main()
{
// 1. Create a map of ints to strings
    INT2STRING theMap;
    INT2STRING::iterator theIterator;


// Fill it with the digits 0 - 9, each mapped to its string counterpart
// Note: value_type is a pair for maps...
    theMap.insert(INT2STRING::value_type(0,"Zero"));
    theMap.insert(INT2STRING::value_type(1,"One"));
    theMap.insert(INT2STRING::value_type(2,"Two"));
    theMap.insert(INT2STRING::value_type(3,"Three"));
    theMap.insert(INT2STRING::value_type(4,"Four"));
    theMap.insert(INT2STRING::value_type(5,"Five"));
    theMap.insert(INT2STRING::value_type(6,"Six"));
    theMap.insert(INT2STRING::value_type(7,"Seven"));
    theMap.insert(INT2STRING::value_type(8,"Eight"));
    theMap.insert(INT2STRING::value_type(9,"Nine"));

            
  for (theIterator=theMap.begin();theIterator!=theMap.end();theIterator++)
     cout << "key " << (*theIterator).first << " value." << (*theIterator).second << endl;
}


acces to key and value via ONE iterator ((*theIterator).first and (*theIterator).second)

nil_dib
0

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jjacksnAuthor Commented:
Isn't that exactly the question I just asked?  
0
nil_dibCommented:
oh, sure it is!
sorry, missunderstoud your comment ...

nil_dib
0
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