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1688. Count of Matches in Tournament

package LeetCode_1688

/**
 * 1688. Count of Matches in Tournament
https://leetcode.com/problems/count-of-matches-in-tournament/

You are given an integer n, the number of teams in a tournament that has strange rules:
1. 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.
2. 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.
 * 
*/ class Solution { /* * solution: follow by rules, Time:O(logn), Space:O(1) * */ fun numberOfMatches(n_: Int): Int { var n = n_ var matches = 0 while (n != 1) { if (n % 2 == 0) { n /= 2 matches += n } else { n
= (n - 1) / 2 matches += n n += 1 } } return matches } }