# 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 . ## 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 ## Code for Maximum number of handshakes in Java:

`// Java program to find maximum number of handshakesimport 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:20190`