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#1648. [USACO06NOV]糟糕的一天Bad Hair Day

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题面翻译

农夫约翰有$N (N \leq 80000)$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$h_i$。第$N$头牛在最前面,而第$1$头牛在最后面。 对于第$i$头牛前面的第$j$头牛,如果$h_i>h_{i+1}$并且$h_i>h_{i+2}$ $\cdots$ $h_i>h_j$,那么认为第$i$头牛可以看到第$i+1$到第$j$头牛

定义$C_i$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$\sum_{i=1}^n C_i$

题目描述

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.

输入格式

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.

输出格式

Line 1: A single integer that is the sum of c1 through cN.

样例 #1

样例输入 #1

6
10
3
7
4
12
2

样例输出 #1

5