{ "data": { "question": { "questionId": "852", "questionFrontendId": "825", "boundTopicId": null, "title": "Friends Of Appropriate Ages", "titleSlug": "friends-of-appropriate-ages", "content": "

There are n persons on a social media website. You are given an integer array ages where ages[i] is the age of the ith person.

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A Person x will not send a friend request to a person y (x != y) if any of the following conditions is true:

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Otherwise, x will send a friend request to y.

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Note that if x sends a request to y, y will not necessarily send a request to x. Also, a person will not send a friend request to themself.

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Return the total number of friend requests made.

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Example 1:

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\nInput: ages = [16,16]\nOutput: 2\nExplanation: 2 people friend request each other.\n
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Example 2:

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\nInput: ages = [16,17,18]\nOutput: 2\nExplanation: Friend requests are made 17 -> 16, 18 -> 17.\n
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Example 3:

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\nInput: ages = [20,30,100,110,120]\nOutput: 3\nExplanation: Friend requests are made 110 -> 100, 120 -> 110, 120 -> 100.\n
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Constraints:

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