Redirecting to
NADOS

Friends Pairing

  Prev   Next 
1. You are given a number n, representing the number of friends.
2. Each friend can stay single or pair up with any of it's friends.
3. You are required to print the number of ways in which these friends can stay single or pair up.
E.g.
1 person can stay single or pair up in 1 way.
2 people can stay singles or pair up in 2 ways. 12 => 1-2, 12.
3 people (123) can stay singles or pair up in 4 ways. 123 => 1-2-3, 12-3, 13-2, 23-1.
Input Format 
A number n
Output Format 
A number representing the number of ways in which n friends can stay single or pair up.
Question Video
Constraints 
0 <= n <= 20
Sample Input 
4
Sample Output 
10


  • Asked in Companies
  • Related Topics






Video Solution

Code Solution

Run
 
Run
Id Name