<p>Given an array of integers <code>temperatures</code> represents the daily temperatures, return <em>an array</em> <code>answer</code> <em>such that</em> <code>answer[i]</code> <em>is the number of days you have to wait after the</em> <code>i<sup>th</sup></code> <em>day to get a warmer temperature</em>. If there is no future day for which this is possible, keep <code>answer[i] == 0</code> instead.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<pre><strong>Input:</strong> temperatures = [73,74,75,71,69,72,76,73]
<strong>Output:</strong> [1,1,4,2,1,1,0,0]
</pre><p><strong class="example">Example 2:</strong></p>
<pre><strong>Input:</strong> temperatures = [30,40,50,60]
<strong>Output:</strong> [1,1,1,0]
</pre><p><strong class="example">Example 3:</strong></p>
<pre><strong>Input:</strong> temperatures = [30,60,90]
<strong>Output:</strong> [1,1,0]
</pre>
<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;=&nbsp;temperatures.length &lt;= 10<sup>5</sup></code></li>
	<li><code>30 &lt;=&nbsp;temperatures[i] &lt;= 100</code></li>
</ul>

class Solution {
private: 
    // marks the temperature and corresponding idx
    stack<int> remainingIdx;

    vector<int> answer;

public:
    vector<int> dailyTemperatures(vector<int>& temperatures) {
        int points = temperatures.size();
        answer = vector<int>(points, 0);

        int idx = 0;
        while(idx < points){
            int currentTemp = temperatures[idx];
            
            //check if current values can fulfill previousl values
            int diff = 1;
            while(!remainingIdx.empty() && diff > 0){
                //
                int stackIdx = remainingIdx.top();

                diff = currentTemp - temperatures[stackIdx];

                if(diff > 0){
                    answer[stackIdx] = idx-stackIdx;
                    remainingIdx.pop();
                }
            }
            
            // push to stack
            remainingIdx.push(idx);

            idx++;
        }

        return answer;
    }
};
109160