Maximum number of handshakes in java

Maximum number of handshakes in Java

Here, we will discuss the maximum number of handshakes in java. The given program will find the maximum number of handshakes in a room. Suppose there are N persons in a room. We have to find the maximum number of Handshakes possible. Given the fact that any two persons shake hand only once.

Example:

N=3

namely A,B,C

A shakes hand with B and C. now B shakes hand with C.Thus total number of ways to shake hands are 2+1 = 3 ways . 

MAximum number of handshakes in Java

Explanation:

Suppose  you entered into a room and there are N numbers of people .You shake hand with your friend so now you have N-1 people left to shake hands with . Similarly for your friend there are N-2 people left and so on.

Thus the above problem can be solved by simple nC2 .

Algorithm :

  •  Start
  •  user is asked to input an integer value n, representing the number of people
  •  calculate answer as  n * (n – 1) / 2 as explained earlier .

    Example: 

    n=3 

    3*(3-1)/2=3 

    thus 3 ways.

  •  Print the output from the above program

  •  End
java program for finding the maximum number of handshakes

Code for Maximum number of handshakes in Java:

// Java program to find maximum number of handshakes

import java.io.*;

import java.util.*;

class handshakes



    // Calculating the maximum number of handshakes 

    static int maxHandshake(int n) 

    { 

        return (n * (n - 1)) / 2; 

    } 
  
    // Driver code 

    public static void main (String[] args) 

    { 

        Scanner sc=newScanner(System.in);

        int n = sc.nextLine(); 

        System.out.println( maxHandshake(n)); 

    } 

output:

20

190