United Cows

The United Cows of Farmer John (UCFJ) are sending a delegation to the International bOvine olympIad (IOI).

There are N cows participating in delegation selection (1N2105). They are standing in a line, and cow i has breed bi.

The delegation will consist of a contiguous interval of at least two cows - that is, cows lr for integers l and r satisfying 1l<rN. The two outermost cows of the chosen interval will be designated as "leaders." To avoid intra-breed conflict, every leader must be of a different breed from the rest of the delegation (leaders or not).

Help the UCFJ determine (for tax reasons) the number of ways they might choose a delegation to send to the IOI.

Input format

The first line contains N.
The second line contains N integers b1,b2,,bN, each in the range [1,N].

Output format

The number of possible delegations, on a single line.

Limits

Subtask # Score Constraints
1 15 N100
2 25 N5000
3 60 No additional constraints

Samples

Sample Input 1 Sample Output 1
7
1 2 3 4 3 2 5
13

Each delegation corresponds to one of the following pairs of leaders:
(1,2),(1,3),(1,4),(1,7),(2,3),(2,4),(3,4),(4,5),(4,6),(4,7),(5,6),(5,7),(6,7).



Submitting .cpp to 'United Cows'


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Time Limit: 1 Seconds
Memory Limit: 1024MB
Your best score: 0
Source: USACO 2021 Open, Gold

Subtask Score
1 15
2 25
3 60
4 0