Build a graph

2.2

78 votes
Algorithms, Graphs
Problem

You are given an integer . Determine if there is an unconnected graph with  vertices that contains at least two connected components and contains the number of edges that is equal to the number of vertices. Each vertex must follow one of these conditions:

  1. Its degree is less than or equal to 1.
  2. It's a cut-vertex.

Note

  • The graph must be simple.
  • Loops and multiple edges are not allowed.

Input format

  • First line: 

Output format

Print Yes if it is an unconnected graph. Otherwise, print No.

Constraints

Sample Input
3
Sample Output
No
Time Limit: 0.5
Memory Limit: 256
Source Limit:
Explanation

There is only one graph with the number of edges equal to the number of vertices (triangle) which is connected.

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