Mr. Malnar is running for mayor of the Tompojevci county. The Tompojevci
county consists of a single village (called Tompojevci), made up of a row of
Mr. Malnar knows all the residents of Tompojevci very well so he knows what the favourite dish of each resident is. That's why for the banquet he'll prepare the meal that is the favourite of the majority of the invited people. However, only the people that get their favourite meal will vote for Mr. Malnar, while the rest will vote for the only other candidate, Mr. Vlado. To win the election, Mr. Malnar needs to get strictly more than half of the votes from the people that voted. The residents that weren't invited to the banquet will forget about the election and are not going to vote.
Mr. Malnar now wants to know how many different ways there are for him to choose the numbers
Input Specification
The first line contains a positive integer
The second line contains
Output Specification
In the only line, print the number of different ways for Mr. Malnar to choose the numbers
Constraints
Subtask | Points | Constraints |
---|---|---|
1 | 10 | |
2 | 15 | |
3 | 15 | |
4 | 70 | No additional constraints. |
Sample Input 1
2
1 1
Sample Output 1
3
Sample Input 2
3
2 1 2
Sample Output 2
4
Explanation for Sample Output 2
The possible choices for
Sample Input 3
5
2 2 1 2 3
Sample Output 3
10
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