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Unordered(FIFO) hash_map implementation . Plz help

Discussion in 'C++' started by veer123, Jan 13, 2009.

  1. veer123

    veer123 New Member

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    Hi want to implement an unordered hashmap ie. FIFO implementation using the standard hash_map library . Below is the sample i tested.Please help me with this.

    #include <hash_map>
    #include <iostream.h>
    int main()
    {
    hash_map<int,int>testMap;
    testMap[1]=1;
    testMap[3]=5;
    testMap[2]=2;
    typedef hash_map<int,int>::iterator hashIter;
    for(hashIter it=testMap.begin();it!=testMap.end();it++)
    {
    cout<<it->second<<"\n";
    }
    }

    The output i get is

    It gives output as

    1
    2
    5

    But I want . ie i want it in the same way i inserted it .

    1
    5
    2

    Any suggestions ?
     
  2. sharmila

    sharmila New Member

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    If you want to display in the same way you inserted, you have to display in the sameway.. 1st, then 3rd and then 2nd values.. not using a for loop by incrementing iterator..
     
  3. veer123

    veer123 New Member

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    After lots of trial and error i have found the answer .

    In hashmap the hashFunc has to be empty . Something like this



    struct hashFunc

    {

    int operator() (int i) const

    {

    }

    };

    This will not sort the data it will be in the manner u insert it….It will be in the stack order. ( What you enter last will be on top ) ...
    :happy::happy::happy:
     

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