## 1. 题目

### Description

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 $h_i$ (1 ≤ $h_i$ ≤ 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:

• 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 $c_i$ denote the number of cows whose hairstyle is visible from cow $i$; please compute the sum of $c_1$ through $c_N$. For this example, the desired is answer $3 + 0 + 1 + 0 + 1 + 0 = 5$.

### Input

Line $1$: The number of cows, $N$.
Lines $2..N+1$: Line $i+1$ contains a single integer that is the height of cow $i$.

### Output

Line $1$: A single integer that is the sum of $c_1$ through $c_N$.

## 2. 题解

### 分析

#### 首递增序列

【注】$N \leq 80000$，故 ${N(N-1) \over 2}$ 会超出 int 的表示范围，所以答案需要用 long long 型表示。