Deque-STL.cpp

#include <iostream>
#include <algorithm> 
#include <deque> 
using namespace std;
void printKMax(int arr[], int n, int k){
    deque<int> q;
	for(int i = 0; i < n; i++)
    {
		for(;!q.empty() && arr[i] > q.back();)
            q.pop_back();  
		q.push_back(arr[i]);  
		if(i >= k && q.front() == arr[i-k])
            q.pop_front();  
		if(i >= k-1)
            printf(i < n-1 ? "%d ":"%d\n", q.front());
	}
}
int main(){
  
   int t;
   cin >> t;
   while(t>0) {
      int n,k;
       cin >> n >> k;
       int i;
       int arr[n];
       for(i=0;i<n;i++)
            cin >> arr[i];
       printKMax(arr, n, k);
       t--;
     }
     return 0;
}