Friends Of Appropriate Ages - Practice Coding | SlaveCode
0
0123456789
0
0123456789
:
0
0123456789
0
0123456789
825. Friends Of Appropriate Ages
Medium
30 Points
Array
Two Pointers
Binary Search
Sorting
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.
A Person x will not send a friend request to a person y (x != y) if any of the following conditions is true:
Otherwise, x will send a friend request to y.
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.
Return the total number of friend requests made.
Examples
Example 1
Input: ages = [16,16]
Output: 2
Explanation: 2 people friend request each other.
Example 2
Input: ages = [16,17,18]
Output: 2
Explanation: Friend requests are made 17 -> 16, 18 -> 17.
Example 3
Input: ages = [20,30,100,110,120]
Output: 3
Explanation: Friend requests are made 110 -> 100, 120 -> 110, 120 -> 100.
Constraints
n == ages.length
1 <= n <= 2 * 104
1 <= ages[i] <= 120
825. Friends Of Appropriate Ages
Medium
30 Points
Array
Two Pointers
Binary Search
Sorting
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.
A Person x will not send a friend request to a person y (x != y) if any of the following conditions is true:
Otherwise, x will send a friend request to y.
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.
Return the total number of friend requests made.
Examples
Example 1
Input: ages = [16,16]
Output: 2
Explanation: 2 people friend request each other.
Example 2
Input: ages = [16,17,18]
Output: 2
Explanation: Friend requests are made 17 -> 16, 18 -> 17.
Example 3
Input: ages = [20,30,100,110,120]
Output: 3
Explanation: Friend requests are made 110 -> 100, 120 -> 110, 120 -> 100.