How to find the most matched values in the set of map?

Question

Hi friends!
I have two vectors
vector<int> V1; vector<int> V2;
and a map<int, set<int>> M1;
I want to select common values from both V1 and V2 and check those values with the set in the map M1.
For example:
V1 contains;
2  4  6  8  9
V2 contains;
4  5  6  9  10 
M1 contains;
1=>1  2  5  9
2=>4
3=>5   10
4=>2  4  8
5=>4   9
6=>4   6
7=>9  12
When we select the common values of V1 and V2 it is 4, 6, 9.
And we search for all 4, 6, 9 from the values of M1 which give more appropriate.
But, no all values in the set of map.
Then, we delete any value from 4, 6, 9, then remaining values would match any values from the map.
From the example, if we delete 6, then remaining 4, 9 will match with 5=>4  9, or if we delete 9, then 6=>4   6. Any one of the keys can be selected.
I know how to select the common values from V1 and V2, but I do not know how to match with the values and select the appropriate key from M1.
Could anyone help me to solve this?

Answer 1

This is not the question you asked, except perhaps in the subject. The subject is not the right place to put key features of the question. It is also important to use the body to ask just the question you want
answered. For example your real question has nothing to do with V1 and V2, just the common vector V (e.g. 4 6 9).
One way to solve your problem would be to create a new map
map<int, set<int>> M2;
with the same keys as M1. Each set of M2 should contain the elements of V that are
not in the corresponding set of M1.
Then pick the key of M2 that has the smallest set. If that set is empty, then the whole of V can be used. Otherwise the smallest set tells which elements of V have to be removed, and which is the desired key of M1.
In your example, key 5 of M2 will contain just 6, so you should remove 6 from V and select key 5.
Yes fine. I tried the following code and it creates the map M2 (NewMyMap in my code). But how to find the smallest set starting from size 1?
#include <vector>
#include <algorithm>
#include <iostream>
#include <map>
#include <set>
using namespace std;
typedef vector<int> IntVec;
typedef set<int> IntSet;
typedef map<int, IntSet> SetMap;
bool IsValueNotInSet(int value, IntSet& S);
SetMap CreatNewSetMap();
IntVec IVec; //This vector is for selecting certain keys from mySet map.
IntVec myVec;
SetMap mySet;
SetMap NewMyMap;
int main()
IVec.push_back(3); IVec.push_back(4); IVec.push_back(5); IVec.push_back(6);
myVec.push_back(4); myVec.push_back(6); myVec.push_back(9);
IntSet tempS;
tempS.insert(1); tempS.insert(2); tempS.insert(5); tempS.insert(9);
mySet.insert(make_pair(1,tempS));
tempS.clear();
tempS.insert(4);
mySet.insert(make_pair(2,tempS));
tempS.clear();
tempS.insert(5); tempS.insert(10);
mySet.insert(make_pair(3,tempS));
tempS.clear();
tempS.insert(2); tempS.insert(4); tempS.insert(8);
mySet.insert(make_pair(4,tempS));
tempS.clear();
tempS.insert(4); tempS.insert(9);
mySet.insert(make_pair(5,tempS));
tempS.clear();
tempS.insert(4); tempS.insert(6);
mySet.insert(make_pair(6,tempS));
tempS.clear();
tempS.insert(9); tempS.insert(12);
mySet.insert(make_pair(7,tempS));
cout<<"MYVEC\n";
cout<<"-------------\n";
for(IntVec::iterator itv = myVec.begin(); itv != myVec.end(); ++itv)
cout<<(*itv)<<" ";
cout<<"\n\n";
cout<<"\nMYSET\n";
cout<<"-------------";
for(map<int,set<int>>::iterator its = mySet.begin(); its != mySet.end(); ++its)
cout << endl << its->first <<" =>";
for(IntSet::iterator sit=its->second.begin();sit!=its->second.end();++sit)
cout<<" "<<(*sit);
cout<<"\n\n";
NewMyMap= CreatNewSetMap();
cout<<"\nNEWMYSET\n";
cout<<"-------------";
for(map<int,set<int>>::iterator its1 = NewMyMap.begin(); its1 != NewMyMap.end(); ++its1)
cout << endl << its1->first <<" =>";
for(IntSet::iterator sit=its1->second.begin();sit!=its1->second.end();++sit)
cout<<" "<<(*sit);
cout<<"\n\n";
return 0;
bool IsValueNotInSet(int value, IntSet& S)
IntSet::iterator it=find (S.begin(), S.end(), value);
if (it!=S.end())
return false;
return true;
SetMap CreatNewSetMap()
IntSet TSet;
for(IntVec::iterator it = IVec.begin(); it != IVec.end(); ++it)
SetMap::iterator its = mySet.find(*it);
if (its != mySet.end())
TSet.clear();
int key = its->first;
IntSet& itset = its->second;
for(IntVec::iterator itv = myVec.begin(); itv != myVec.end(); ++itv)
if(IsValueNotInSet((*itv), itset))
TSet.insert(*itv);
NewMyMap.insert(make_pair(key,TSet));
return NewMyMap;