问题描述 |
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Kim have an undirected complete graph with n vertices drawn on a paper. A complete graph is a simple undirected graph in which every pair of distinct vertices is connected by a unique edge. One day he his naughty little brother came again and erased some vertices and edges. |
输入描述 |
输出描述 |
For each case, print a line contains the answer. |
样例输入复制样例 |
2 |
样例输出 |
2 |
提示说明 |
The original graph in simple input 1 look like this: and after delete: so there are 2 connected components. |
来源 |
2017年第八届福建省大学生程序设计竞赛热身赛 |