Author:  А. Жихарева  Time limit:  2 sec  
Input file:  Standard input  Memory limit:  512 Mb  
Output file:  Standard output 
There are N points on a circle, represented by numbers a_{i}, where a_{i} — direction from center to point i, measured in 1/100th parts of degree.
Your program must choose a set of pairs of points so that:
First line of input contains integer N.
Second line contains N integers a_{i} — directions from center to points, measured in 1/100th parts of degree.
Output must contain two integers S and M, where S — largest total arc length, M — number of selected pairs.
Next, output must contain M pairs of integers — pairs of point indices corresponding to the ends of each arc. Indices start with 1. The order of points in pair may be arbitrary.
If there are several optimal solutions, output any of them.
2 ≤ N ≤ 5000, 0 ≤ a_{i} < 36000
No.  Standard input  Standard output 

1 


2 

