<p>Given an integer array <code>nums</code> and an integer <code>k</code>, return <em>the length of the shortest non-empty <strong>subarray</strong> of </em><code>nums</code><em> with a sum of at least </em><code>k</code>. If there is no such <strong>subarray</strong>, return <code>-1</code>.</p>

<p>A <strong>subarray</strong> is a <strong>contiguous</strong> part of an array.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<pre><strong>Input:</strong> nums = [1], k = 1
<strong>Output:</strong> 1
</pre><p><strong class="example">Example 2:</strong></p>
<pre><strong>Input:</strong> nums = [1,2], k = 4
<strong>Output:</strong> -1
</pre><p><strong class="example">Example 3:</strong></p>
<pre><strong>Input:</strong> nums = [2,-1,2], k = 3
<strong>Output:</strong> 3
</pre>
<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= nums.length &lt;= 10<sup>5</sup></code></li>
	<li><code>-10<sup>5</sup> &lt;= nums[i] &lt;= 10<sup>5</sup></code></li>
	<li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li>
</ul>

class Solution {
public:
    int shortestSubarray(vector<int>& nums, int k) {
        vector<long long> numsLong(nums.begin(), nums.end());
        int n = numsLong.size();
        vector<int> dp(n, 0);
        deque<pair<long long, int>> mq;
        mq.push_back(make_pair(0, -1));
        
        // Prefix Sum
        for (int i = 1; i < n; i++) {
            if ( numsLong[i] >= k) return 1;
            numsLong[i] += numsLong[i - 1];
        }

        cout << "Hello" << endl;


        int ans = 1e9;
        for (int i = 0; i < n; i++) {
            while (!mq.empty() && numsLong[i] - mq.front().first >= k) {
                cout << "Hello" << endl;
                ans = min(i - mq.front().second, ans);
                mq.pop_front();
            }

            while (!mq.empty() && numsLong[i] <= mq.back().first) {
                mq.pop_back();
            }

            mq.push_back(make_pair(numsLong[i], i));
        }
        return (ans != 1e9) ? ans : -1;
    }
};
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