Data Structure Array: Sort elements by frequency

http://www.geeksforgeeks.org/sort-elements-by-frequency-set-2/

 #include <iostream>
 #include <vector>
 #include <algorithm>
 #include <queue>
 #include <stack>
 #include <string>
 #include <fstream>
 #include <map>
 using namespace std;

 void printarray(int arr[], int n) {
     map<int, int> S;
     for (int i = ; i < n; i++) {
         if (S.find(arr[i]) == S.end()) S[arr[i]] = ;
         else S[arr[i]]++;
     }
     map<int, vector<int> > T;
     for (map<int, int>::iterator it = S.begin(); it != S.end(); it++) {
         T[it->second].push_back(it->first);
     }
     for (map<int, vector<int> >::iterator it = T.end(); it != T.begin();) {
         it--;
         vector<int> tmp = it->second;
         for (int j = ; j < tmp.size(); j++) {
             for (int k = ; k < it->first; k++) cout << tmp[j] << " ";
         }
     }
 }

 int main() {
     int arr[] = {, , , , , , , , , , };
     printarray(arr, );
     return ;
 }