Friend Request

Similar Problems:

Given an array Ages of length n, where the first i elements represent the age of the individual i Find total number of friend requests sent by this n person. There are some requirements:

- if Age(B) <= (1/2)Age(A) + 7, A will not send a request to B.
- if Age(B) > Age(A), A will not send a request to B.
- if Age(B) < 100 and Age(A) > 100, A will not send a request to B.
- If it does not satisfy 1,2,3, then A will send a request to B

Notice

- Ages.length <= 1000
- Everyone’s age is greater than 0, less than 150

Example

Given Ages = [10,39,50], return 1.

Explanation: Only people of age 50 will send friend requests to people of age 39.

Given Ages = [101,79,102], return 1.

Explanation: Only people of age 102 will send friend requests to people of age 101.

Github: code.dennyzhang.com

Credits To: lintcode.com

Leave me comments, if you have better ways to solve.

## https://code.dennyzhang.com/friend-request ## Basic Ideas: two loop ## Complexity: Time O(n^2), Space O(1) class Solution: """ @param ages: The ages @return: The answer """ def friendRequest(self, ages): res = 0 for i in range(len(ages)): for j in range(len(ages)): if i == j: continue if ages[j]<=(1/2)*ages[i]+7: continue if ages[j]>ages[i]: continue if ages[j]<100 and ages[i]>100: continue res += 1 return res