Leetcode 暑期bb班

495 回覆
251 Like 31 Dislike
2022-05-31 21:45:02
係,你個方法time complexity更好
搵唔到有其他easy可以introduce heap
如果你有題目可以幫到一個做左leetcode 5日熟習heap嘅
歡迎你po上黎
2022-05-31 21:47:27
我係唔識,我都係操下leetcode咋
不過而家想大家學heap,呢兩題用heap都係straightforward
你有無更好方法推介比我地點學algo?
2022-05-31 21:49:09
多謝你分享
2022-05-31 23:44:44
python好方便,default係按順序sort
2022-05-31 23:45:53
操heap,queue stack 先
之後bfs dfs,之後先linkedlist
linkedlist好似比較少問
2022-05-31 23:55:05
你個solution係O(n*m)
Counting係O(m)
O(n log m)應該要用Binary search去probe column index
睇下邊個column多d 1
2022-05-31 23:58:16
Day 5 review (heap)

https://leetcode.com/problems/the-k-weakest-rows-in-a-matrix/
呢題最簡單可以用sort做,不過我地個topic係用heap
loop每一個row,數有幾多個1,之後heappush (用max heap,因為我地想pop最大嘅數)
如果個heap多過k行,就heappop
最後heappop返攞答案,再reverse
你個solution係O(n*m)
Counting係O(n)
O(m log n)應該要用Binary search去probe column index
睇下邊個column多d 1
2022-06-01 00:05:52
Scanning都係O(n*m)
2022-06-01 00:44:56
2022-06-01 00:59:04
2022-06-01 02:50:12
可以用binary search揾每行有幾多個1O(m log n + m log m)
2022-06-01 06:43:59
我 interview都冇 準備執包袱返香港
2022-06-01 07:15:42
agree binary search is the better approach
2022-06-01 07:18:04
junior role system design...
2022-06-01 11:11:06
2022-06-01 11:45:06
python set 等於 java hashset?
2022-06-01 13:18:55
巴打,Typescript好似無heap,想問係唔係應該用其他language比較好。
2022-06-01 20:29:18
Day 6 Review (Heap)

https://leetcode.com/problems/k-closest-points-to-origin/
呢題用一個max heap去keep住啲points,heap可以儲list係入面,default係順序排,例如 [2,3] < [3, 1] and [2,4] > [2,2]
儲到個heap超過k個point,就pop (因為max heap,所以會pop走最遠)
去到最後攞返個heap入面嘅x y就ok

https://leetcode.com/problems/minimum-operations-to-halve-array-sum/
用max heap去keep track最大嘅數,之後pop最大個數除二,repeat until減左超過原本sum嘅一半
2022-06-01 20:29:28
yes
吹水台自選台熱 門最 新手機台時事台政事台World體育台娛樂台動漫台Apps台遊戲台影視台講故台健康台感情台家庭台潮流台美容台上班台財經台房屋台飲食台旅遊台學術台校園台汽車台音樂台創意台硬件台電器台攝影台玩具台寵物台軟件台活動台電訊台直播台站務台黑 洞