2775More is better

2775   More is better

题目描述

Mr Wang wants some boys to help him with a project. Because the project is rather complex, the more boys come, the better it will be. Of course there are certain requirements.Mr Wang selected a room big enough to hold the boys. The boy who are not been chosen has to leave the room immediately. There are 10000000 boys in the room numbered from 1 to 10000000 at the very beginning. After Mr Wang's selection any two of them who are still in this room should be friends (direct or indirect), or there is only one boy left. Given all the direct friend-pairs, you should decide the best way.

输入格式:

The first line of the input contains an integer n (0 ≤ n ≤ 100 000) - the number of direct friend-pairs. The following n lines each contains a pair of numbers A and B separated by a single space that suggests A and B are direct friends. (A ≠ B, 1 ≤ A, B ≤ 10000000)

输出格式:

The output in one line contains exactly one integer equals to the maximum number of boys Mr Wang may keep.

输入样例 复制
3
1 3
1 5
2 5
4
3 2
3 4
1 6
2 6

输出样例 复制
4
5

说明

8
27
通过提交
时空限制1000ms/128mb
题目来源
评测方式在线评测
题目类型
难        度