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 total = 0;
while(n>1){
total+=n/2;
if(n%2!=0 && n != 1){
n++;
}
n=n/2;
}
return total;
}
}Time Complexity: O(logn)
Space Complexity: O(1)
