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Abhishek Chaudhary

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Find Players With Zero or One Losses

You are given an integer array `matches` where `matches[i] = [winneri, loseri]` indicates that the player `winneri` defeated player `loseri` in a match.

Return a list `answer` of size `2` where:

• `answer[0]` is a list of all players that have not lost any matches.
• `answer[1]` is a list of all players that have lost exactly one match.

The values in the two lists should be returned in increasing order.

Note:

• You should only consider the players that have played at least one match.
• The testcases will be generated such that no two matches will have the same outcome.

Example 1:

Input: matches = [[1,3],[2,3],[3,6],[5,6],[5,7],[4,5],[4,8],[4,9],[10,4],[10,9]]
Output: [[1,2,10],[4,5,7,8]]
Explanation:
Players 1, 2, and 10 have not lost any matches.
Players 4, 5, 7, and 8 each have lost one match.
Players 3, 6, and 9 each have lost two matches.

Example 2:

Input: matches = [[2,3],[1,3],[5,4],[6,4]]
Output: [[1,2,5,6],[]]
Explanation:
Players 1, 2, 5, and 6 have not lost any matches.
Players 3 and 4 each have lost two matches.

Constraints:

• `1 <= matches.length <= 105`
• `matches[i].length == 2`
• `1 <= winneri, loseri <= 105`
• `winneri != loseri`
• All `matches[i]` are unique.

SOLUTION:

``````import bisect
from collections import defaultdict

class Solution:
def findWinners(self, matches: List[List[int]]) -> List[List[int]]:
played = defaultdict(int)
won = defaultdict(int)
for winner, loser in matches:
won[winner] += 1
played[winner] += 1
played[loser] += 1