Given an array of integers arr and an integer k. Find the least number of unique integers after removing exactly k elements.
Example 1:
Input: arr = [5,5,4], k = 1 Output: 1 Explanation: Remove the single 4, only 5 is left.
Example 2:
Input: arr = [4,3,1,1,3,3,2], k = 3 Output: 2 Explanation: Remove 4, 2 and either one of the two 1s or three 3s. 1 and 3 will be left.
Constraints:
1 <= arr.length <= 10^51 <= arr[i] <= 10^90 <= k <= arr.lengthclass Solution { public int findLeastNumOfUniqueInts(int[] arr, int k) { Map<Integer, Integer> map = new HashMap<>(); for (int n : arr) map.put(n, map.getOrDefault(n, 0) + 1); List<Integer> l = new ArrayList<>(map.keySet()); Collections.sort(l, (a, b) -> map.get(a) - map.get(b)); int n = map.size(), remove = 0, idx = 0; while (k > 0 && idx < n) { k -= map.get(l.get(idx++)); if (k >= 0) remove++; } return n - remove; } }
这就是差距吧。。
1481. Least Number of Unique Integers after K Removals
原文：https://www.cnblogs.com/wentiliangkaihua/p/13156774.html