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Java-based LeetCode algorithm problem solutions, regularly updated

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package g0401_0500.s0475_heaters;

// #Medium #Array #Sorting #Binary_Search #Two_Pointers
// #2022_07_20_Time_9_ms_(99.61%)_Space_44.9_MB_(84.55%)

import java.util.Arrays;

/**
 * 475 - Heaters\.
 *
 * Medium
 *
 * Winter is coming! During the contest, your first job is to design a standard heater with a fixed warm radius to warm all the houses.
 *
 * Every house can be warmed, as long as the house is within the heater's warm radius range.
 *
 * Given the positions of `houses` and `heaters` on a horizontal line, return _the minimum radius standard of heaters so that those heaters could cover all houses._
 *
 * **Notice** that all the `heaters` follow your radius standard, and the warm radius will the same.
 *
 * **Example 1:**
 *
 * **Input:** houses = [1,2,3], heaters = [2]
 *
 * **Output:** 1
 *
 * **Explanation:** The only heater was placed in the position 2, and if we use the radius 1 standard, then all the houses can be warmed.
 *
 * **Example 2:**
 *
 * **Input:** houses = [1,2,3,4], heaters = [1,4]
 *
 * **Output:** 1
 *
 * **Explanation:** The two heater was placed in the position 1 and 4. We need to use radius 1 standard, then all the houses can be warmed.
 *
 * **Example 3:**
 *
 * **Input:** houses = [1,5], heaters = [2]
 *
 * **Output:** 3
 *
 * **Constraints:**
 *
 * *   1 <= houses.length, heaters.length <= 3 * 10⁴
 * *   1 <= houses[i], heaters[i] <= 10⁹
**/
public class Solution {
    public int findRadius(int[] houses, int[] heaters) {
        int res = 0;
        int m = houses.length;
        int n = heaters.length;
        int hs = 0;
        int ht = 0;
        Arrays.sort(houses);
        Arrays.sort(heaters);
        if (n == 1) {
            return Math.max(Math.abs(houses[0] - heaters[0]), Math.abs(houses[m - 1] - heaters[0]));
        }
        while (hs < m && ht < n - 1) {
            if (houses[hs] <= heaters[ht]) {
                res = Math.max(heaters[ht] - houses[hs], res);
                hs++;
            } else if (houses[hs] <= heaters[ht + 1]) {
                res =
                        Math.max(
                                res,
                                Math.min(houses[hs] - heaters[ht], heaters[ht + 1] - houses[hs]));
                hs++;
            } else {
                ht++;
            }
        }
        if (ht == n - 1) {
            res = Math.max(res, houses[m - 1] - heaters[n - 1]);
        }
        return res;
    }
}