Largest Values From Labels
<p>You are given <code>n</code> item&#39;s value and label as two integer arrays <code>values</code> and <code>labels</code>. You are also given two integers <code>numWanted</code> and <code>useLimit</code>.</p>

<p>Your task is to find a subset of items with the <strong>maximum sum</strong> of their values such that:</p>

<ul>
	<li>The number of items is <strong>at most</strong> <code>numWanted</code>.</li>
	<li>The number of items with the same label is <strong>at most</strong> <code>useLimit</code>.</li>
</ul>

<p>Return the maximum sum.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<div class="example-block">
<p><strong>Input:</strong> <span class="example-io">values = [5,4,3,2,1], labels = [1,1,2,2,3], numWanted = 3, useLimit = 1</span></p>

<p><strong>Output:</strong> <span class="example-io">9</span></p>

<p><strong>Explanation:</strong></p>

<p>The subset chosen is the first, third, and fifth items with the sum of values 5 + 3 + 1.</p>
</div>

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

<div class="example-block">
<p><strong>Input:</strong> <span class="example-io">values = [5,4,3,2,1], labels = [1,3,3,3,2], numWanted = 3, useLimit = 2</span></p>

<p><strong>Output:</strong> <span class="example-io">12</span></p>

<p><strong>Explanation:</strong></p>

<p>The subset chosen is the first, second, and third items with the sum of values 5 + 4 + 3.</p>
</div>

<p><strong class="example">Example 3:</strong></p>

<div class="example-block">
<p><strong>Input:</strong> <span class="example-io">values = [9,8,8,7,6], labels = [0,0,0,1,1], numWanted = 3, useLimit = 1</span></p>

<p><strong>Output:</strong> <span class="example-io">16</span></p>

<p><strong>Explanation:</strong></p>

<p>The subset chosen is the first and fourth items with the sum of values 9 + 7.</p>
</div>

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

<ul>
	<li><code>n == values.length == labels.length</code></li>
	<li><code>1 &lt;= n &lt;= 2 * 10<sup>4</sup></code></li>
	<li><code>0 &lt;= values[i], labels[i] &lt;= 2 * 10<sup>4</sup></code></li>
	<li><code>1 &lt;= numWanted, useLimit &lt;= n</code></li>
</ul>
Greedy; Array; Hash Table; Counting; Sorting
function largestValsFromLabels(
    values: number[],
    labels: number[],
    numWanted: number,
    useLimit: number,
): number {
    const n = values.length;
    const pairs = new Array(n);
    for (let i = 0; i < n; ++i) {
        pairs[i] = [values[i], labels[i]];
    }
    pairs.sort((a, b) => b[0] - a[0]);
    const cnt: Map<number, number> = new Map();
    let ans = 0;
    for (let i = 0, num = 0; i < n && num < numWanted; ++i) {
        const [v, l] = pairs[i];
        if ((cnt.get(l) || 0) < useLimit) {
            cnt.set(l, (cnt.get(l) || 0) + 1);
            ++num;
            ans += v;
        }
    }
    return ans;
}
