#D11014. Three Occurrences
Three Occurrences
Three Occurrences
You are given an array a consisting of n integers. We denote the subarray a[l..r] as the array [a_l, a_{l + 1}, ..., a_r] (1 ≤ l ≤ r ≤ n).
A subarray is considered good if every integer that occurs in this subarray occurs there exactly thrice. For example, the array [1, 2, 2, 2, 1, 1, 2, 2, 2] has three good subarrays:
- a[1..6] = [1, 2, 2, 2, 1, 1];
- a[2..4] = [2, 2, 2];
- a[7..9] = [2, 2, 2].
Calculate the number of good subarrays of the given array a.
Input
The first line contains one integer n (1 ≤ n ≤ 5 ⋅ 10^5).
The second line contains n integers a_1, a_2, ..., a_n (1 ≤ a_i ≤ n).
Output
Print one integer — the number of good subarrays of the array a.
Examples
Input
9 1 2 2 2 1 1 2 2 2
Output
3
Input
10 1 2 3 4 1 2 3 1 2 3
Output
0
Input
12 1 2 3 4 3 4 2 1 3 4 2 1
Output
1
inputFormat
Input
The first line contains one integer n (1 ≤ n ≤ 5 ⋅ 10^5).
The second line contains n integers a_1, a_2, ..., a_n (1 ≤ a_i ≤ n).
outputFormat
Output
Print one integer — the number of good subarrays of the array a.
Examples
Input
9 1 2 2 2 1 1 2 2 2
Output
3
Input
10 1 2 3 4 1 2 3 1 2 3
Output
0
Input
12 1 2 3 4 3 4 2 1 3 4 2 1
Output
1
样例
10
1 2 3 4 1 2 3 1 2 3
0