Sliding_window_maximum.cpp

#include <bits/stdc++.h>
using namespace std;

// function
void maxSlidingWindow(vector<int> &nums, int k)
{

    vector<int> ans;

    int i = 0, j = 0;
    int n = nums.size();
    int mx, pm;
    deque<int> q;

    while (j < n)
    {

        while (!q.empty() && q.back() < nums[j])
        {
            q.pop_back();
        }
        q.push_back(nums[j]);

        if (j - i + 1 < k)
        {
            j++;
        }
        else if (j - i + 1 == k)
        {
            ans.push_back(q.front());

            if (nums[i] == q.front())
            {

                q.pop_front();
            }
            i++;
            j++;
        }
    }
    for (int i = 0; i < ans.size(); i++)
    {
        cout << ans[i] << " ";
    }
}

// driver code
int main()
{
    vector<int> v = {1, 3, -1, -3, 5, 3, 6, 7};
    maxSlidingWindow(v, 3);
    return 0;
}