3707: P2866 [USACO06NOV]Bad Hair Day S

Some of Farmer John's N cows (1 ≤ N ≤ 80,000) are having a bad hair day! Since each cow is self-conscious about her messy hairstyle, FJ wants to count the number of other cows that can see the top of other cows' heads.

Each cow i has a specified height hi (1 ≤ hi ≤ 1,000,000,000) and is standing in a line of cows all facing east (to the right in our diagrams). Therefore, cow i can see the tops of the heads of cows in front of her (namely cows i+1, i+2, and so on), for as long as these cows are strictly shorter than cow i.

Consider this example:

 - - - - -   - - -   - - - - - - - - - - - -
1 2 3 4 5 6

Cows facing right -->

Cow#1 can see the hairstyle of cows #2, 3, 4

Cow#2 can see no cow's hairstyle

Cow#3 can see the hairstyle of cow #4

Cow#4 can see no cow's hairstyle

Cow#5 can see the hairstyle of cow 6

Cow#6 can see no cows at all!

Let ci denote the number of cows whose hairstyle is visible from cow i; please compute the sum of c1 through cN.For this example, the desired is answer 3 + 0 + 1 + 0 + 1 + 0 = 5.

农夫约翰有�(�≤80000)N(N≤80000)头奶牛正在过乱头发节。每一头牛都站在同一排面朝东方，而且每一头牛的身高为ℎ�hi。第�N头牛在最前面，而第11头牛在最后面。 对于第�i头牛前面的第�j头牛，如果ℎ�>ℎ�+1hi>hi+1并且ℎ�>ℎ�+2hi>hi+2 ⋯⋯ ℎ�>ℎ�hi>hj，那么认为第�i头牛可以看到第�+1i+1到第�j头牛
定义��Ci为第�i头牛所能看到的别的牛的头发的数量。请帮助农夫约翰求出∑�=1���∑i=1nCi

Line 1: The number of cows, N.

Lines 2..N+1: Line i+1 contains a single integer that is the height of cow i.

6
10
3
7
4
12
2

5