_1103.java

package com.fishercoder.solutions;

import java.util.HashMap;
import java.util.Map;

/**
 * 1103. Distribute Candies to People
 *
 * We distribute some number of candies, to a row of n = num_people people in the following way:
 * We then give 1 candy to the first person, 2 candies to the second person, and so on until we give n candies to the last person.
 * Then, we go back to the start of the row, giving n + 1 candies to the first person, n + 2 candies to the second person,
 * and so on until we give 2 * n candies to the last person.
 * This process repeats (with us giving one more candy each time, and moving to the start of the row
 * after we reach the end) until we run out of candies.
 * The last person will receive all of our remaining candies (not necessarily one more than the previous gift).
 * Return an array (of length num_people and sum candies) that represents the final distribution of candies.
 *
 * Example 1:
 * Input: candies = 7, num_people = 4
 * Output: [1,2,3,1]
 * Explanation:
 * On the first turn, ans[0] += 1, and the array is [1,0,0,0].
 * On the second turn, ans[1] += 2, and the array is [1,2,0,0].
 * On the third turn, ans[2] += 3, and the array is [1,2,3,0].
 * On the fourth turn, ans[3] += 1 (because there is only one candy left), and the final array is [1,2,3,1].
 *
 * Example 2:
 * Input: candies = 10, num_people = 3
 * Output: [5,2,3]
 * Explanation:
 * On the first turn, ans[0] += 1, and the array is [1,0,0].
 * On the second turn, ans[1] += 2, and the array is [1,2,0].
 * On the third turn, ans[2] += 3, and the array is [1,2,3].
 * On the fourth turn, ans[0] += 4, and the final array is [5,2,3].
 *
 * Constraints:
 * 1 <= candies <= 10^9
 * 1 <= num_people <= 1000
 * */
public class _1103 {
    public static class Solution1 {
        public int[] distributeCandies(int candies, int numPeople) {
            Map<Integer, Integer> map = new HashMap<>();
            int candy = 1;
            while (candies > 0) {
                for (int person = 1; person <= numPeople && candies > 0; person++, candy++) {
                    if (candies < candy) {
                        map.put(person, map.getOrDefault(person, 0) + candies);
                        candies -= candy;
                        break;
                    } else {
                        map.put(person, map.getOrDefault(person, 0) + candy);
                        candies -= candy;
                    }
                }
            }
            int[] result = new int[numPeople];
            for (int i = 1; i <= numPeople; i++) {
                if (map.containsKey(i)) {
                    result[i - 1] = map.get(i);
                } else {
                    result[i - 1] = 0;
                }
            }
            return result;
        }
    }
}