Description

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

Solution

class Solution:
    def numberOfMatches(self, n: int) -> int:
        c = 0
        while n > 1:
            c += n // 2
            if n % 2 == 0:
                n //= 2
            else:
                n = n // 2 + 1     
        return c