Codeforces Round 306 (Div. 2)
D
Regular Bridge
Codeforces
1900
原题
← CE →
翻译中…

An undirected graph is called $*k*$-regular, if the degrees of all its vertices are equal $*k*$. An edge of a connected graph is called a bridge, if after removing it the graph is being split into two connected components.

翻译中…

Build a connected undirected $*k*$-regular graph containing at least one bridge, or else state that such graph doesn't exist.

翻译中…

Input

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The single line of the input contains integer $*k*$ ($1 ≤ *k* ≤ 100$) — the required degree of the vertices of the regular graph.

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Output

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Print "NO" (without quotes), if such graph doesn't exist.

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Otherwise, print "YES" in the first line and the description of any suitable graph in the next lines.

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The description of the made graph must start with numbers $*n*$ and $*m*$ — the number of vertices and edges respectively.

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Each of the next $*m*$ lines must contain two integers, $*a*$ and $*b*$ ($1 ≤ *a*, *b* ≤ *n*$, $*a* ≠ *b*$), that mean that there is an edge connecting the vertices $*a*$ and $*b*$. A graph shouldn't contain multiple edges and edges that lead from a vertex to itself. A graph must be connected, the degrees of all vertices of the graph must be equal $*k*$. At least one edge of the graph must be a bridge. You can print the edges of the graph in any order. You can print the ends of each edge in any order.

翻译中…

The constructed graph must contain at most $10^{6}$ vertices and $10^{6}$ edges (it is guaranteed that if at least one graph that meets the requirements exists, then there also exists the graph with at most $10^{6}$ vertices and at most $10^{6}$ edges).

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Note

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In the sample from the statement there is a suitable graph consisting of two vertices, connected by a single edge.

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样例

Input #1
1
Output #1
YES
2 1
1 2
InputCopy OutputCopy
题目信息
题号
550D
时间限制
2 s
内存限制
256 MB
标签
构造
图论
模拟

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