Number of matches required to find the winner

Given a number N which represents the number of players participating in a Badminton match. The task is to determine the number of matches required to determine the Winner. In each Match 1 player is knocked out.

Examples:

Input:  N = 4
Output: Matches played = 3
(As after each match only N - 1 players left)

Input: N = 9
Output: Matches played = 8

Approach: Since, after each match, one player is knocked out. So to get the winner, n-1 players should be knocked out and for which n-1 matches to be played.

Below is the implementation of the above approach:

C++

// C++ implementation of above approach
#include <bits/stdc++.h>
using namespace std;

// Function that will tell
// no. of matches required
int noOfMatches(int N)
{
    return N - 1;
}

// Driver code
int main()
{
    int N = 8;

    cout << "Matches played = " << noOfMatches(N);

    return 0;
}

Java

// Java implementation of above approach
import java.io.*;

class GFG
{

// Function that will tell
// no. of matches required
static int noOfMatches(int N)
{
    return N - 1;
}

// Driver code
public static void main (String[] args)
{
    int N = 8;
    System.out.println ("Matches played = " +
                          noOfMatches(N));
}
}

// This code is contributed by jit_t

Python3

# Python 3 implementation of
# above approach

# Function that will tell
# no. of matches required
def noOfMatches(N) :

    return N - 1

# Driver code
if __name__ == "__main__" :

    N = 8

    print("Matches played =",
              noOfMatches(N))

# This code is contributed
# by ANKITRAI1

C#

//C# implementation of above approach
using System;

public class GFG{


// Function that will tell
// no. of matches required
static int noOfMatches(int N)
{
    return N - 1;
}

// Driver code

    static public void Main (){
    int N = 8;
    Console.WriteLine("Matches played = " +
                        noOfMatches(N));
}
}

// This code is contributed by ajit

PHP

<?php
// PHP implementation of above approach

// Function that will tell
// no. of matches required
function noOfMatches($N)
{
    return ($N - 1);
}

// Driver code
$N = 8;
echo "Matches played = ",
         noOfMatches($N);

// This code is contributed by akt_mit
?>

Javascript

<script>

// Javascript implementation of above approach

// Function that will tell
// no. of matches required
function noOfMatches(N)
{
    return N - 1;
}

// Driver code
var N = 8;

document.write("Matches played = " +
               noOfMatches(N));

// This code is contributed by rutvik_56

</script>

Output:

Matches played = 7

Time Complexity: O(1)
Auxiliary Space: O(1)