There are N guard places on a wall. There are N-1 wall sections between them.
The walls are identified from 1 to N. A wall section between i. and i+1. guard places is identified by i.
A wallsection is verified when there is guard on at least one of its end.
A wallsection is protected if there are guards on both end.

Write a C++ application which helps to answer the following questions:

1) Number of verified wallsections
2) How many lookout need a guard that the whole wall (every wallsection) is verified?
3) Which wallsection (with its identifier) is the first what is not verified?
	(0 if there is not a wallsection)
4) Where starts and ends the longest (continuously) protected wallsection(s)?
	(The first one is enough or it is 0 if there is not protected wallsection)

Example input
N=9
1 0 6 0 0 0 2 2 1

Output of the example
6
1
4
7 9