CF140C.New Year Snowmen
普及/提高-
通过率:0%
AC君温馨提醒
该题目为【codeforces】题库的题目,您提交的代码将被提交至codeforces进行远程评测,并由ACGO抓取测评结果后进行展示。由于远程测评的测评机由其他平台提供,我们无法保证该服务的稳定性,若提交后无反应,请等待一段时间后再进行重试。
题目描述
As meticulous Gerald sets the table and caring Alexander sends the postcards, Sergey makes snowmen. Each showman should consist of three snowballs: a big one, a medium one and a small one. Sergey's twins help him: they've already made n snowballs with radii equal to r1 , r2 , ..., rn . To make a snowman, one needs any three snowballs whose radii are pairwise different. For example, the balls with radii 1 , 2 and 3 can be used to make a snowman but 2 , 2 , 3 or 2 , 2 , 2 cannot. Help Sergey and his twins to determine what maximum number of snowmen they can make from those snowballs.
输入格式
The first line contains integer n ( 1<=n<=105 ) — the number of snowballs. The next line contains n integers — the balls' radii r1 , r2 , ..., rn ( 1<=ri<=109 ). The balls' radii can coincide.
输出格式
Print on the first line a single number k — the maximum number of the snowmen. Next k lines should contain the snowmen's descriptions. The description of each snowman should consist of three space-separated numbers — the big ball's radius, the medium ball's radius and the small ball's radius. It is allowed to print the snowmen in any order. If there are several solutions, print any of them.
输入输出样例
输入#1
7 1 2 3 4 5 6 7
输出#1
2 3 2 1 6 5 4
输入#2
3 2 2 3
输出#2
0