Data Structure Array: Maximum of all subarrays of size k

http://www.geeksforgeeks.org/maximum-of-all-subarrays-of-size-k/

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

 void printKMax(int arr[], int n, int k) {
     deque<int> S;
     S.push_back();
     for (int i = ; i < k; i++) {
         while (!S.empty() && arr[i] >= arr[S.back()]) S.pop_back();
         S.push_back(i);
     }
     for (int i = k; i < n; i++) {
         cout << arr[S.front()] << " ";
         while (!S.empty() && i - k >= S.front()) S.pop_front();
         while (!S.empty() && arr[S.back()] <= arr[i]) S.pop_back();
         S.push_back(i);
     }
     cout << arr[S.front()] << endl;
 }

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