leetcode1395 - Count Number of Teams - medium
作者:互联网
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
class Solution { public: int numTeams(vector<int>& rating) { int n = rating.size(); int res = 0; for (int j = 0; j<n; j++){ int l = 0; int r = 0; for (int i=0; i<j; i++){ if (rating[i] < rating[j]) l++; } for (int k=j+1; k<n; k++){ if (rating[k] > rating[j]) r++; } res += l*r + (j-l)*(n-1-j-r); } return res; } };
标签:Count,rating,given,medium,form,int,Teams,Input,soldiers 来源: https://www.cnblogs.com/xuningwang/p/13943374.html