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825. Friends Of Appropriate Ages

https://leetcode.com/problems/friends-of-appropriate-ages/ Some people will make friend requests. The list of their ages is given and  ages[i]  is the age of the ith person.  Person A will NOT friend request person B (B != A) if any of the following conditions are true: age[B] <= 0.5 * age[A] + 7 age[B] > age[A] age[B] > 100 && age[A] < 100 Otherwise, A will friend request B. Note that if A requests B, B does not necessarily request A.  Also, people will not friend request themselves. How many total friend requests are made? Example 1: Input: [16,16] Output: 2 Explanation: 2 people friend request each other. Example 2: Input: [16,17,18] Output: 2 Explanation: Friend requests are made 17 -> 16, 18 -> 17. Example 3: Input: [20,30,100,110,120] Output: Explanation: Friend requests are made 110 -> 100, 120 -> 110, 120 -> 100. Notes: 1 <= ages.length <= 20000 . 1 <= ages[i] <= 120 . --- Intuition Running a cross product of age array wi