LeetCode 1395. Count Number of Teams

There are n soldiers standing in a line. Each soldier is assigned a unique rating value.

You have to form a team of 3 soldiers amongst them under the following rules:

Choose 3 soldiers with index (i, j, k) with rating (rating[i], rating[j], rating[k]).
A team is valid if: (rating[i] < rating[j] < rating[k]) or (rating[i] > rating[j] > rating[k]) where (0 <= i < j < k < n).
Return the number of teams you can form given the conditions. (soldiers can be part of multiple teams).

Example 1:

Input: rating = [2,5,3,4,1]
Output: 3
Explanation: We can form three teams given the conditions. (2,3,4), (5,4,1), (5,3,1).
Example 2:

Input: rating = [2,1,3]
Output: 0
Explanation: We can't form any team given the conditions.
Example 3:

Input: rating = [1,2,3,4]
Output: 4

Constraints:

n == rating.length
1 <= n <= 200
1 <= rating[i] <= 10^5

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int numTeams(int* rating, int ratingSize){
    int sum = 0;
    for(int mid = 1; mid<ratingSize-1; ++mid){
        int leftSmall = 0, leftGreat = 0;
        int rightSmall = 0, rightGreat = 0;
        for(int i = 0; i<ratingSize; ++i){
            if(i==mid){
                continue;
            }
            if(i<mid){
                if(rating[i]<rating[mid]){
                    ++leftSmall;
                }
                else if(rating[i]>rating[mid]){
                     ++leftGreat;
                }
            }
            else{
                if(rating[i]<rating[mid]){
                    ++rightSmall;
                }
                else if(rating[i]>rating[mid]){
                     ++rightGreat;
                }
            }
        }
        sum += leftSmall*rightGreat + leftGreat*rightSmall;
    }
    return sum;
}


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