<p>You are given the <code>head</code> of a linked list.</p>

<p>Remove every node which has a node with a greater value anywhere to the right side of it.</p>

<p>Return <em>the </em><code>head</code><em> of the modified linked list.</em></p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2022/10/02/drawio.png" style="width: 631px; height: 51px;" />
<pre>
<strong>Input:</strong> head = [5,2,13,3,8]
<strong>Output:</strong> [13,8]
<strong>Explanation:</strong> The nodes that should be removed are 5, 2 and 3.
- Node 13 is to the right of node 5.
- Node 13 is to the right of node 2.
- Node 8 is to the right of node 3.
</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> head = [1,1,1,1]
<strong>Output:</strong> [1,1,1,1]
<strong>Explanation:</strong> Every node has value 1, so no nodes are removed.
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li>The number of the nodes in the given list is in the range <code>[1, 10<sup>5</sup>]</code>.</li>
	<li><code>1 &lt;= Node.val &lt;= 10<sup>5</sup></code></li>
</ul>

class Solution {
public:
    ListNode* removeNodes(ListNode* head) {
        

        // tc: O(n)
        // sc: (2n)

        ListNode* temp = head;
        ListNode* it = head;

        stack<int> stk;
        

        while( it != NULL )
        {
            stk.push(it->val);
            it = it->next;
        }

        int mx = 0;
        vector<int> v;

        while( !stk.empty() )
        {
            int top = stk.top();
            if( mx <= top )
            {
                v.push_back(top);
                mx = top;
            }

            stk.pop();
        }

        reverse(v.begin(),v.end());

        for(auto i : v)
        {
            temp -> val = i;
            it = temp;
            temp = temp->next;
        }
        if( it )
        it->next = NULL;

        return head;

    }
};
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