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Java-based LeetCode algorithm problem solutions, regularly updated

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package g2501_2600.s2561_rearranging_fruits;

// #Hard #Array #Hash_Table #Greedy #2023_08_21_Time_36_ms_(96.81%)_Space_64.6_MB_(12.77%)

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * 2561 - Rearranging Fruits\.
 *
 * Hard
 *
 * You have two fruit baskets containing `n` fruits each. You are given two **0-indexed** integer arrays `basket1` and `basket2` representing the cost of fruit in each basket. You want to make both baskets **equal**. To do so, you can use the following operation as many times as you want:
 *
 * *   Chose two indices `i` and `j`, and swap the i^th fruit of `basket1` with the j^th fruit of `basket2`.
 * *   The cost of the swap is `min(basket1[i],basket2[j])`.
 *
 * Two baskets are considered equal if sorting them according to the fruit cost makes them exactly the same baskets.
 *
 * Return _the minimum cost to make both the baskets equal or_ `-1` _if impossible._
 *
 * **Example 1:**
 *
 * **Input:** basket1 = [4,2,2,2], basket2 = [1,4,1,2]
 *
 * **Output:** 1
 *
 * **Explanation:** Swap index 1 of basket1 with index 0 of basket2, which has cost 1. Now basket1 = [4,1,2,2] and basket2 = [2,4,1,2]. Rearranging both the arrays makes them equal.
 *
 * **Example 2:**
 *
 * **Input:** basket1 = [2,3,4,1], basket2 = [3,2,5,1]
 *
 * **Output:** -1
 *
 * **Explanation:** It can be shown that it is impossible to make both the baskets equal.
 *
 * **Constraints:**
 *
 * *   `basket1.length == bakste2.length`
 * *   1 <= basket1.length <= 10⁵
 * *   1 <= basket1[i],basket2[i] <= 10⁹
**/
public class Solution {
    public long minCost(int[] basket1, int[] basket2) {
        int n = basket1.length;
        Map cnt = new HashMap<>();
        for (int i = 0; i < n; ++i) {
            cnt.merge(basket1[i], 1, Integer::sum);
            cnt.merge(basket2[i], -1, Integer::sum);
        }
        int mi = 1 << 30;
        List nums = new ArrayList<>();
        for (var e : cnt.entrySet()) {
            int x = e.getKey();
            int v = e.getValue();
            if (v % 2 != 0) {
                return -1;
            }
            for (int i = Math.abs(v) / 2; i > 0; --i) {
                nums.add(x);
            }
            mi = Math.min(mi, x);
        }
        Collections.sort(nums);
        int m = nums.size();
        long ans = 0;
        for (int i = 0; i < m / 2; ++i) {
            ans += Math.min(nums.get(i), mi * 2);
        }
        return ans;
    }
}