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Java-based LeetCode algorithm problem solutions, regularly updated

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package g1601_1700.s1688_count_of_matches_in_tournament;

// #Easy #Math #Simulation #2022_04_15_Time_0_ms_(100.00%)_Space_39.4_MB_(81.03%)

/**
 * 1688 - Count of Matches in Tournament\.
 *
 * Easy
 *
 * You are given an integer `n`, the number of teams in a tournament that has strange rules:
 *
 * *   If the current number of teams is **even** , each team gets paired with another team. A total of `n / 2` matches are played, and `n / 2` teams advance to the next round.
 * *   If the current number of teams is **odd** , one team randomly advances in the tournament, and the rest gets paired. A total of `(n - 1) / 2` matches are played, and `(n - 1) / 2 + 1` teams advance to the next round.
 *
 * Return _the number of matches played in the tournament until a winner is decided._
 *
 * **Example 1:**
 *
 * **Input:** n = 7
 *
 * **Output:** 6
 *
 * **Explanation:** Details of the tournament:
 *
 * - 1st Round: Teams = 7, Matches = 3, and 4 teams advance.
 *
 * - 2nd Round: Teams = 4, Matches = 2, and 2 teams advance.
 *
 * - 3rd Round: Teams = 2, Matches = 1, and 1 team is declared the winner.
 *
 * Total number of matches = 3 + 2 + 1 = 6.
 *
 * **Example 2:**
 *
 * **Input:** n = 14
 *
 * **Output:** 13
 *
 * **Explanation:** Details of the tournament:
 *
 * - 1st Round: Teams = 14, Matches = 7, and 7 teams advance.
 *
 * - 2nd Round: Teams = 7, Matches = 3, and 4 teams advance.
 *
 * - 3rd Round: Teams = 4, Matches = 2, and 2 teams advance.
 *
 * - 4th Round: Teams = 2, Matches = 1, and 1 team is declared the winner.
 *
 * Total number of matches = 7 + 3 + 2 + 1 = 13.
 *
 * **Constraints:**
 *
 * *   `1 <= n <= 200`
**/
public class Solution {
    public int numberOfMatches(int n) {
        int matches = 0;
        while (n > 1) {
            if (n % 2 == 0) {
                matches += n / 2;
                n /= 2;
            } else {
                matches += (n - 1) / 2;
                n = (n + 1) / 2;
            }
        }
        return matches;
    }
}